Corner module apparatus for vehicle

ABSTRACT

Disclosed is a corner module apparatus for a vehicle. The corner module apparatus includes processors configured to obtain a steering angle, obtain a lever ratio indicating whether a front wheel and a rear wheel of a bicycle model defined with respect to a vehicle are inphase or reverse-phased and indicating a steering angle ratio. The corner module apparatus also includes a controller configured to calculate a front wheel heading angle of the bicycle model from the steering angle, calculate a rear wheel heading angle of the bicycle model based on the calculated front wheel heading angle and the lever ratio, calculate first to fourth target angles of a left front wheel, a right front wheel, a left rear wheel, and a right rear wheel of the vehicle by expanding the bicycle model to a four-wheel vehicle model, and independently control steering of each of the four wheels.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 USC § 119(a) of KoreanPatent Application Nos. 10-2021-0162191 and 10-2021-0188608, filed onNov. 23, 2021 and Dec. 27, 2021, respectively, in the KoreanIntellectual Property Office, the entire disclosures of which are herebyincorporated by reference for all purposes.

BACKGROUND 1. Field

The present disclosure relates to a corner module apparatus for avehicle in which driving, braking, steering, and suspension systems areintegrated.

2. Description of Related Art

An electric vehicle in many instances refers to an eco-friendly vehicledevoid of the discharge of exhaust gas. A high-voltage battery forsupplying energy for driving, a motor for driving for generatingrotatory power from power outputted by the high-voltage battery, etc.are mounted in (or on) the electric vehicle. Movement of the electricvehicle is in most instances driven by the rotation power of the motorbeing delivered to wheels through a driving shaft.

Recently, an in-wheel motor vehicle in which a motor is directlyinstalled inside a wheel so that power of the motor is directlydelivered to the wheel has been introduced. The in-wheel motor takesinto consideration advantages in which weight of the vehicle can bereduced and an energy loss in a power transfer process can be reducedwhile omitting a power transfer unit of an intermediate stage, such as adecelerator or a differential gear. Furthermore, a wheel in whichbraking, steering, and suspension systems are integrated in addition toa driving system is also being actively developed.

SUMMARY

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

In one general aspect, here is provided a corner module apparatus for avehicle. The corner module apparatus includes processors configured toobtain a steering angle, obtain a lever ratio indicating whether a frontwheel and a rear wheel of a bicycle model defined with respect to avehicle are inphase or reverse-phased and indicating a steering angleratio. The corner module apparatus also includes a controller configuredto calculate a front wheel heading angle of the bicycle model from thesteering angle, calculate a rear wheel heading angle of the bicyclemodel based on the calculated front wheel heading angle and the leverratio, calculate first to fourth target angles of a left front wheel, aright front wheel, a left rear wheel, and a right rear wheel of thevehicle by expanding the bicycle model to a four-wheel vehicle model,and independently control steering of each of the four wheels by usingthe calculated first to fourth target angles. The calculation of thefirst to fourth target angles is determined in differentiated ways basedon a value of the lever ratio.

The controller may be configured to calculate the front wheel headingangle by multiplying the steering angle by a preset value of steeringsensitivity.

The lever ratio may have a value of −1 to 1, a sign of the lever ratiomay indicate whether the front wheel and the rear wheel of the bicyclemodel are inphase and reversed-phased, and a size of the lever ratio mayindicate a steering angle ratio between the front wheel and the rearwheel of the bicycle model.

The controller may be configured to calculate the first to fourth targetangles by determining a steering control mode in differentiated waysbased on the value of the lever ratio. The steering control mode mayinclude a front-wheel steering mode corresponding to a steering controlmode when the lever ratio is 0, a four-wheel inphase steering modecorresponding to a steering control mode when the lever ratio is greaterthan 0 and equal to or less than 1, and a four-wheel reversed-phasesteering mode corresponding to a steering control mode when the leverratio is equal to or greater than −1 and less than 0.

In the front-wheel steering mode, the controller may be configured tocalculate the first and second target angles by applying the Ackermangeometry model to the front wheel heading angle, and to calculate thethird and fourth target angles as a neutral angle indicative of alongitudinal direction of the vehicle.

In the four-wheel reversed-phase steering mode and the four-wheelinphase steering mode in a state in which the lever ratio is greaterthan 0 and less than 1, the controller may be configured to (i)calculate the first and second target angles by applying the Ackermangeometry model to the front wheel heading angle, and (ii) calculate therear wheel heading angle of the bicycle model by applying the leverratio to the front wheel heading angle, and calculate the third andfourth target angles by applying the Ackerman geometry model to thecalculated rear wheel heading angle.

The controller may calculate the first to fourth target angles as thefront wheel heading angle in the four-wheel inphase steering mode in astate in which the lever ratio is 1.

In another general aspect, here is provided a method of operating acorner module apparatus for a vehicle. The method includes obtaining asteering angle, obtaining a lever ratio indicating whether a front wheeland a rear wheel of a bicycle model defined with respect to a vehicleare inphase or reverse-phased and indicating a steering angle ratio,calculating, by a controller, a front wheel heading angle of the bicyclemodel from the steering angle and calculating a rear wheel heading angleof the bicycle model based on the calculated front wheel heading angleand the lever ratio, calculating, by the controller, first to fourthtarget angles of a left front wheel, a right front wheel, a left rearwheel, and a right rear wheel of the vehicle by expanding the bicyclemodel to a four-wheel vehicle model, and independently controlling, bythe controller, steering of each of the four wheels of the vehicle byusing the calculated first to fourth target angles. The calculation ofthe first to fourth target angles is determined in differentiated waysbased on a value of the lever ratio.

Calculating of the front wheel heading angle and the rear wheel headingangle of the bicycle model may further include calculating the frontwheel heading angle by multiplying the steering angle by a preset valueof steering sensitivity.

The lever ratio may have a value of −1 to 1, a sign of the lever ratiomay indicate whether the front wheel and the rear wheel of the bicyclemodel are inphase and reversed-phased, and a size of the lever ratio mayindicate a steering angle ratio between the front wheel and the rearwheel of the bicycle model.

Calculating of the first to fourth target angles may further includecalculating the first to fourth target angles by determining a steeringcontrol mode in differentiated ways based on the value of the leverratio. The steering control mode may include a front-wheel steering modecorresponding to a steering control mode when the lever ratio is 0, afour-wheel inphase steering mode corresponding to a steering controlmode when the lever ratio is greater than 0 and equal to or less than 1,and a four-wheel reversed-phase steering mode corresponding to asteering control mode when the lever ratio is equal to or greater than−1 and less than 0.

Calculating the first to fourth target angles, when the steering controlmode of the vehicle is the front-wheel steering mode, may furtherinclude calculating the first and second target angles by applying theAckerman geometry model to the front wheel heading angle, andcalculating the third and fourth target angles as a neutral angleindicative of a longitudinal direction of the vehicle.

Calculating of the first to fourth target angles, when the steeringcontrol mode of the vehicle is the four-wheel reversed-phase steeringmode or the four-wheel inphase steering mode in a state in which thelever ratio is greater than 0 and less than 1, may further includecalculating the first and second target angles by applying the Ackermangeometry model to the front wheel heading angle, and (ii) calculatingthe rear wheel heading angle of the bicycle model by applying the leverratio to the front wheel heading angle, and calculating the third andfourth target angles by applying the Ackerman geometry model to thecalculated rear wheel heading angle.

Calculating the first to fourth target angles, when the steering controlmode of the vehicle is the four-wheel inphase steering mode in a statein which the lever ratio is 1, may further include calculating the firstto fourth target angles as the front wheel heading angle.

In another general aspect, here is provided a corner module apparatusfor a vehicle. The corner module apparatus includes processorsconfigured to obtain a steering angle, and obtain a lever ratioindicating whether a front wheel and a rear wheel of a bicycle modeldefined with respect to a vehicle are inphase or reverse-phased andindicating a steering angle ratio, the lever ratio being configured tobe changed based on a manipulation input. The corner module apparatusalso includes a controller configured to calculate a front wheel headingangle and a rear wheel heading angle of the bicycle model based on thesteering angle and the lever ratio, calculate first to fourth targetangles of a left front wheel, a right front wheel, a left rear wheel,and a right rear wheel of the vehicle by using the front wheel headingangle and the rear wheel heading angle, and independently controlsteering of each of the four wheels of the vehicle by using thecalculated first to fourth target angles. The controller is configuredto calculate the first to fourth target angles as values that varydepending on transition of a steering control mode in response tochanges in the lever ratio.

The transition of the steering control mode may be in response to thelever ratio being changed in a process of the vehicle driving.

The lever ratio may have a value of −1 to 1, and the steering controlmode may include a front-wheel steering mode corresponding to a steeringcontrol mode when the lever ratio is 0, a four-wheel inphase steeringmode corresponding to a steering control mode when the lever ratio isgreater than 0 and equal to or less than 1, and a four-wheelreversed-phase steering mode corresponding to a steering control modewhen the lever ratio is equal to or greater than −1 and less than 0.

When the transition of the steering control mode is caused because thelever ratio is changed in the process of the vehicle driving, thecontroller may be configured to perform the transition of the steeringcontrol mode during a preset excess time by controlling change speeds ofthe steering angles of the four wheels at a preset control speed.

The controller may be further configured to calculate the front wheelheading angle of the bicycle model from the steering angle, calculatethe rear wheel heading angle of the bicycle model based on thecalculated front wheel heading angle and the lever ratio, and calculatethe first to fourth target angles of the left front wheel, the rightfront wheel, the left rear wheel, and the right rear wheel of thevehicle by expanding the bicycle model to a four-wheel vehicle model.

Other features and aspects will be apparent from the following detaileddescription, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view schematically illustrating a configuration of avehicle including a corner module apparatus for a vehicle according toan embodiment of the present disclosure.

FIG. 2 is a perspective view schematically illustrating a configurationof a vehicle including a corner module apparatus for a vehicle accordingto an embodiment of the present disclosure.

FIG. 3 is a perspective view schematically illustrating a configurationof a main platform according to an embodiment of the present disclosure.

FIGS. 4 and 5 are enlarged views schematically illustratingconfigurations of a main fastening part according to an embodiment ofthe present disclosure.

FIG. 6 is a perspective view schematically illustrating a configurationof a first corner module platform and a second corner module platformaccording to an embodiment of the present disclosure.

FIGS. 7 and 8 are enlarged views schematically illustratingconfigurations of a first corner module fastening part and a secondcorner module fastening part according to an embodiment of the presentdisclosure.

FIG. 9 is a perspective view schematically illustrating a configurationof a corner module according to a first embodiment of the presentdisclosure.

FIG. 10 is a perspective view illustrating a configuration of the cornermodule according to the first embodiment of the present disclosure at aview different from that of the configuration of FIG. 9 .

FIG. 11 is a front view schematically illustrating a configuration ofthe corner module according to the first embodiment of the presentdisclosure.

FIG. 12 is a side view schematically illustrating a configuration of thecorner module according to the first embodiment of the presentdisclosure.

FIG. 13 is an exploded perspective view schematically illustrating aconfiguration of the corner module according to the first embodiment ofthe present disclosure.

FIG. 14 is a cross-sectional view schematically illustrating aconfiguration of a steering driving unit according to the firstembodiment of the present disclosure.

FIGS. 15, 16A and 16B are operation diagrams schematically illustratingan operating process of the corner module according to the firstembodiment of the present disclosure.

FIG. 17 is a diagram schematically illustrating a configuration of avehicle including a corner module apparatus for a vehicle according toanother embodiment of the present disclosure.

FIG. 18 is a diagram schematically illustrating a configuration of afirst corner module platform and a second corner module platformaccording to another embodiment of the present disclosure.

FIGS. 19 and 20 are enlarged views schematically illustrating aconfiguration of a first corner module extension fastening part and asecond corner module extension fastening part according to an embodimentof the present disclosure.

FIG. 21 is a diagram schematically illustrating a configuration of avehicle including a corner module apparatus for a vehicle according tostill another embodiment of the present disclosure.

FIG. 22 is a block diagram for describing a function of a corner moduleapparatus for a vehicle according to an embodiment of the presentdisclosure.

FIG. 23 is a diagram schematically illustrating a series of processes ofcalculating first to fourth target angles in a first application(individual steering architecture) of a corner module apparatus for avehicle according to an embodiment of the present disclosure.

FIG. 24 is a diagram illustrating first to fourth target angles in afront-wheel steering mode in the first application (individual steeringarchitecture) of a corner module apparatus for a vehicle according to anembodiment of the present disclosure.

FIGS. 25 and 26 are diagrams illustrating first to fourth target anglesin a four-wheel inphase steering mode in the first application(individual steering architecture) of a corner module apparatus for avehicle according to an embodiment of the present disclosure.

FIGS. 27 and 28 are diagrams illustrating first to fourth target anglesin a four-wheel reversed-phase steering mode in the first application(individual steering architecture) of a corner module apparatus for avehicle according to an embodiment of the present disclosure.

FIG. 29 is a flowchart for describing an operating method in the firstapplication (individual steering architecture) of a corner moduleapparatus for a vehicle according to an embodiment of the presentdisclosure.

FIGS. 30 to 33 are diagrams illustrating a relation between a slope anda location of a vehicle in a second application (a braking mechanismthrough individual steering) of a corner module apparatus for a vehicleaccording to an embodiment of the present disclosure.

FIGS. 34 to 36 are diagrams illustrating the state in which wheels havebeen aligned according to a direction angle in the second application(the braking mechanism through individual steering) a corner moduleapparatus for a vehicle according to an embodiment of the presentdisclosure.

FIG. 37 is a flowchart for describing an operating method in the secondapplication (the braking mechanism through individual steering) of acorner module apparatus for a vehicle according to an embodiment of thepresent disclosure.

FIG. 38 is a diagram illustrating a method of determining a variablegain in a third application (a posture control mechanism for improvingstraight driving performance) of a corner module apparatus for a vehicleaccording to an embodiment of the present disclosure.

FIG. 39 is a flowchart for describing an operating method in the thirdapplication (the posture control mechanism for improving straightdriving performance) of a corner module apparatus for a vehicleaccording to an embodiment of the present disclosure.

FIG. 40 is a flowchart for describing an operating method in a fourthapplication (a posture control mechanism for solving a slip) of a cornermodule apparatus for a vehicle according to an embodiment of the presentdisclosure.

FIG. 41 is a diagram illustrating a process of calculating distanceinformation and center target curvature in a fifth application (a targettrajectory generation and tracking control mechanism) of a corner moduleapparatus for a vehicle according to an embodiment of the presentdisclosure.

FIG. 42 is a diagram illustrating a process of calculating left targetcurvature and right target curvature in the fifth application (thetarget trajectory generation and tracking control mechanism) of a cornermodule apparatus for a vehicle according to an embodiment of the presentdisclosure.

FIG. 43 is a diagram illustrating a process of calculating a targetsteering angle in the fifth application (the target trajectorygeneration and tracking control mechanism) of a corner module apparatusfor a vehicle according to an embodiment of the present disclosure.

FIG. 44 is a block diagram illustrating a method of independentlycontrolling the steering of each wheel in the fifth application (thetarget trajectory generation and tracking control mechanism) of a cornermodule apparatus for a vehicle according to an embodiment of the presentdisclosure.

FIG. 45 is a flowchart for describing an operating method in the fifthapplication (the target trajectory generation and tracking controlmechanism) of a corner module apparatus for a vehicle according to anembodiment of the present disclosure.

Throughout the drawings and the detailed description, unless otherwisedescribed or provided, the same drawing reference numerals will beunderstood to refer to the same elements, features, and structures. Thedrawings may not be to scale, and the relative size, proportions, anddepiction of elements in the drawings may be exaggerated for clarity,illustration, and convenience.

DETAILED DESCRIPTION

The following detailed description is provided to assist the reader ingaining a comprehensive understanding of the methods, apparatuses,and/or systems described herein. However, various changes,modifications, and equivalents of the methods, apparatuses, and/orsystems described herein will be apparent after an understanding of thedisclosure of this application. For example, the sequences of operationsdescribed herein are merely examples, and are not limited to those setforth herein, but may be changed as will be apparent after anunderstanding of the disclosure of this application, with the exceptionof operations necessarily occurring in a certain order.

The features described herein may be embodied in different forms and arenot to be construed as being limited to the examples described herein.Rather, the examples described herein have been provided merely toillustrate some of the many possible ways of implementing the methods,apparatuses, and/or systems described herein that will be apparent afteran understanding of the disclosure of this application.

Advantages and features of the present disclosure and methods ofachieving the advantages and features will be clear with reference toembodiments described in detail below together with the accompanyingdrawings. However, the present disclosure is not limited to theembodiments disclosed herein but will be implemented in various forms.The embodiments of the present disclosure are provided so that thepresent disclosure is completely disclosed, and a person with ordinaryskill in the art can fully understand the scope of the presentdisclosure. The present disclosure will be defined only by the scope ofthe appended claims. Meanwhile, the terms used in the presentspecification are for explaining the embodiments, not for limiting thepresent disclosure.

Terms, such as first, second, A, B, (a), (b) or the like, may be usedherein to describe components. Each of these terminologies is not usedto define an essence, order or sequence of a corresponding component butused merely to distinguish the corresponding component from othercomponent(s). For example, a first component may be referred to as asecond component, and similarly the second component may also bereferred to as the first component.

Throughout the specification, when a component is described as being“connected to,” or “coupled to” another component, it may be directly“connected to,” or “coupled to” the other component, or there may be oneor more other components intervening therebetween. In contrast, when anelement is described as being “directly connected to,” or “directlycoupled to” another element, there can be no other elements interveningtherebetween.

The singular forms “a”, “an”, and “the” are intended to include theplural forms as well, unless the context clearly indicates otherwise. Itwill be further understood that the terms “comprises/comprising” and/or“includes/including” when used herein, specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components and/or groups thereof.

Spatially relative terms such as “above,” “upper,” “below,” and “lower”may be used herein for ease of description to describe one element'srelationship to another element as shown in the figures. Such spatiallyrelative terms are intended to encompass different orientations of thedevice in use or operation in addition to the orientation depicted inthe figures. For example, if the device in the figures is turned over,an element described as being “above” or “upper” relative to anotherelement will then be “below” or “lower” relative to the other element.Thus, the term “above” encompasses both the above and below orientationsdepending on the spatial orientation of the device. The device may alsobe oriented in other ways (for example, rotated 90 degrees or at otherorientations), and the spatially relative terms used herein are to beinterpreted accordingly.

The terminology used herein is for describing various examples only, andis not to be used to limit the disclosure. The articles “a,” “an,” and“the” are intended to include the plural forms as well, unless thecontext clearly indicates otherwise. The terms “comprises,” “includes,”and “has” specify the presence of stated features, numbers, operations,members, elements, and/or combinations thereof, but do not preclude thepresence or addition of one or more other features, numbers, operations,members, elements, and/or combinations thereof.

Due to manufacturing techniques and/or tolerances, variations of theshapes shown in the drawings may occur. Thus, the examples describedherein are not limited to the specific shapes shown in the drawings, butinclude changes in shape that occur during manufacturing.

The features of the examples described herein may be combined in variousways as will be apparent after an understanding of the disclosure ofthis application. Further, although the examples described herein have avariety of configurations, other configurations are possible as will beapparent after an understanding of the disclosure of this application.

Hereinafter, embodiments of a vehicle including a corner moduleapparatus for a vehicle and an operating method of the corner moduleapparatus for a vehicle according to the present disclosure will bedescribed with reference to the accompanying drawings.

Various embodiments are directed to providing a corner module apparatusfor a vehicle, which can freely adjust the number and alignment ofwheels to suit a purpose of a vehicle.

Furthermore, various embodiments are directed to providing a cornermodule apparatus for a vehicle, which can independently controloperations of each wheel.

FIG. 1 is a front view schematically illustrating a configuration of avehicle including a corner module apparatus for a vehicle according toan embodiment of the present disclosure. FIG. 2 is a perspective viewschematically illustrating a configuration of a vehicle including acorner module apparatus for a vehicle according to an embodiment of thepresent disclosure.

Referring to FIGS. 1 and 2 , the vehicle including a corner moduleapparatus for a vehicle according to an embodiment of the presentdisclosure includes a corner module apparatus 1 for a vehicle, a top hat2, and a door part 3.

The corner module apparatus 1 for a vehicle according to an embodimentof the present disclosure includes a frame module 100 and a cornermodule 200.

The frame module 100 is installed on the lower side of a vehicle body,and generally supports the corner module 200, a battery 400, and aninverter 500.

Referring to FIG. 2 , the frame module 100 according to the presentembodiment includes a main platform 1100, a first corner module platform1200A, and a second corner module platform 1200B.

The main platform 1100 is installed on the lower side of the vehiclebody. The battery 400 for supplying a power source to the corner module200 described later is mounted within the main platform 1100. The mainplatform 1100 may have a highly rigid material, such as metal, so thatmain platform can sufficiently withstand weight applied from the battery400. The battery 400 is formed to have a lower height than the mainplatform 1100.

FIG. 3 is a perspective view schematically illustrating a configurationof the main platform 1100 according to an embodiment of the presentdisclosure.

Referring to FIG. 3 , the main platform 1100 according to the presentembodiment includes a main plate 1110, a main wheel housing 1120, and amain fastening part 1130.

The main plate 1110 forms an external appearance of a central part ofthe main platform 1100, and generally supports the main wheel housing1120 described later. The main plate 1110 according to an embodiment ofthe present disclosure may be formed to have a form of a flat plate thatis disposed in parallel the ground. The battery 400 is seated on the topof the main plate 1110, and the inverter 500 may be seated thereon, ifnecessary. The design of the area of the main plate 1110 may bevariously changed depending on the size of the vehicle body, the size ofthe battery 400, etc.

The main wheel housing 1120 extends from the main plate 1110, andprovides a space in which the corner module 200 is accommodated. Themain wheel housing 1120 according to the present embodiment may beformed to have a form of a pillar that is perpendicularly upwardextended from the top of the main plate 1110. More specifically, themain wheel housing 1120 is disposed on the corner side of the main plate1110, and is formed to have an outside surface thereof opened. Forexample, the main wheel housing 1120 may be extended to the top of thecorner of the main plate 1110 with a cross-sectional form of anapproximately “¬” form as illustrated in FIG. 3 . Accordingly, the mainwheel housing 1120 may provide a space in which the corner module 200 isaccommodated.

The top of the main wheel housing 1120 is formed to have a form of aflat plate that is disposed in parallel to the main plate 1110.Accordingly, the main wheel housing 1120 may provide a space in whichthe main fastening part 1130 described later may be formed on the top ofthe main wheel housing 1120.

The main wheel housing 1120 may be provided in plural. The plurality ofmain wheel housings 1120 may be disposed on the plurality of cornersides of the main plate 1110, respectively.

The main fastening part 1130 is provided in the main plate 1110 and themain wheel housing 1120, and is fastened to the first corner moduleplatform 1200A and the second corner module platform 1200B describedlater.

FIGS. 4 and 5 are enlarged views schematically illustratingconfigurations of the main fastening part according to an embodiment ofthe present disclosure.

Referring to FIGS. 3 to 5 , the main fastening part 1130 according tothe present embodiment includes an upper main fastening part 1131 and alower main fastening part 1132.

The upper main fastening part 1131 according to the present embodimentmay be formed to have a form of a groove that is concavely recessed andformed from an outside surface of the main wheel housing 1120. The uppermain fastening part 1131 is perpendicularly downward extended from thetop of the main wheel housing 1120. The upper main fastening part 1131may have a cross-sectional form having a step form so that the uppermain fastening part 1131 is locked and coupled with a first cornermodule upper-fastening part 1231A and a second corner moduleupper-fastening part 1231B described later. The upper main fasteningpart 1131 is disposed at the end of the main wheel housing 1120 disposedto face the first corner module platform 1200A and the second cornermodule platform 1200B described later. The upper main fastening part1131 may be provided in plural, and may be individually provided in themain wheel housings 1120, respectively.

The lower main fastening part 1132 according to the present embodimentmay be formed to have a form of a groove that is concavely recessed andformed from the outside surface of the main plate 1110. The lower mainfastening part 1132 may have a cross-sectional form having a step formso that lower main fastening part 1132 is locked and coupled with afirst corner module lower-fastening part 1232A and a second cornermodule lower-fastening part 1232B described later.

The lower main fastening part 1132 is extended in a direction oppositeto a direction of the upper main fastening part 1131. More specifically,the lower main fastening part 1132 is perpendicularly upward extendedfrom the lower side of the main plate 1110. Accordingly, when beingfastened to a first corner module fastening part 1230A and a secondcorner module fastening part 1230B described later, the upper mainfastening part 1131 and the lower main fastening part 1132 can preventthe first corner module fastening part 1230A and the second cornermodule fastening part 1230B from deviating in any one direction.

The lower main fastening part 1132 is provided in pair, and is disposedat the ends of the main plate 1110 disposed to face the first cornermodule platform 1200A and the second corner module platform 12008described later, respectively.

The first corner module platform 1200A and the second corner moduleplatform 12008 are detachably coupled to both sides of the main platform1100, respectively. The first corner module platform 1200A and thesecond corner module platform 1200B have the corner modules 200described later coupled to lower sides thereof, respectively, andsupport the corner modules 200. The corner module 200 and the inverter500 that converts DC power supplied from the battery 400 into AC powerand transmits the AC power to the corner module 200 are mounted withineach of the first corner module platform 1200A and the second cornermodule platform 1200B. The inverter 500 is formed to have a lower heightthan the first corner module platform 1200A and the second corner moduleplatform 12008. The first corner module platform 1200A and the secondcorner module platform 1200B may have a highly rigid material, such asmetal, so that the first corner module platform 1200A and the secondcorner module platform 12008 can sufficiently withstand weight appliedfrom the corner module 200 and the battery 400.

FIG. 6 is a perspective view schematically illustrating a configurationof the first corner module platform and the second corner moduleplatform according to an embodiment of the present disclosure.

Referring to FIG. 6 , the first corner module platform 1200A accordingto the present embodiment includes a first corner module plate 1210A, afirst corner module wheel housing 1220A, and the first corner modulefastening part 1230A.

The first corner module plate 1210A forms an external appearance of acentral part of the first corner module platform 1200A, and generallysupports the first corner module wheel housing 1220A described later.The first corner module plate 1210A according to the present embodimentmay be formed to have a form of a flat plate that is disposed inparallel to the ground. The inverter 500 is seated on the top of thefirst corner module plate 1210A, and the battery 400 may be seatedthereon, if necessary. The design of the area of the first corner moduleplate 1210A may be variously changed the size of the main plate 1110,the size of the inverter 500, etc.

The first corner module wheel housing 1220A extends from the firstcorner module plate 1210A and provides a space in which the cornermodule 200 is accommodated. The first corner module wheel housing 1220Aaccording to the present embodiment may be formed to have a form of aplate that extends upward from the top of the main plate 1110. The firstcorner module wheel housing 1220A may be provided in pair, and may bedisposed at the ends of the first corner module plate 1210A in a widthdirection thereof, respectively.

The first corner module wheel housing 1220A is provided with a firstmounting plate 1221A that supports the corner module 200. The firstmounting plate 1221A may be formed to have a form of a flat plate thatextends in the width direction of the first corner module plate 1210Afrom the top of the first corner module wheel housing 1220A. The firstmounting plate 1221A is disposed in parallel to the first corner moduleplate 1210A. The lower side of the first mounting plate 1221A isdetachably coupled to the corner module 200 by bolting coupling, etc.

In this case, the first corner module wheel housing 1220A may beextended to the outside of the first corner module plate 1210A in thewidth direction thereof with a cross-sectional form having anapproximately “¬” form as illustrated in FIG. 6 . Accordingly, the firstcorner module wheel housing 1220A may provide a space in which thecorner module 200 is accommodated.

The first corner module fastening part 1230A is provided in the firstcorner module plate 1210A and the first corner module wheel housing1220A, and is fastened to the main fastening part 1130 disposed on oneside of the main platform 1100. When the main platform 1100 and thefirst corner module platform 1200A are assembled, the first cornermodule fastening part 1230A is disposed at a location that faces themain fastening part 1130 disposed on the one side of the main platform1100. The first corner module fastening part 1230A is locked and coupledwith the main fastening part 1130 disposed on the one side of the mainplatform 1100 as the first corner module platform 1200A mutually comesinto contact with the main platform 1100 in a direction parallel to thelength direction of a vehicle. Accordingly, the main fastening part 1130and the first corner module fastening part 1230A can improve assemblyperformance of the main platform 1100 and the first corner moduleplatform 1200A.

FIGS. 7 and 8 are enlarged views schematically illustratingconfigurations of the first corner module fastening part and the secondcorner module fastening part according to an embodiment of the presentdisclosure.

Referring to FIGS. 6 to 8 , the first corner module fastening part 1230Aaccording to an embodiment of the present disclosure includes the firstcorner module upper-fastening part 1231A and the first corner modulelower-fastening part 1232A.

The first corner module upper-fastening part 1231A according to thepresent embodiment may be formed to have a form of a protrusion thatprotrudes from the outside surface of the first corner module wheelhousing 1220A. More specifically, the first corner moduleupper-fastening part 1231A is transversely extended from the end of thefront or rear of the first mounting plate 1221A, more specifically, anend disposed to face the end of the main platform 1100 on one sidethereof. The first corner module upper-fastening part 1231A is insertedinto the upper main fastening part 1131 disposed on the one side of themain platform 1100 as the first corner module platform 1200A comes intocontact with the main platform 1100 in the direction parallel to thelength direction of the vehicle. In this case, the first corner moduleupper-fastening part 1231A may have a shape having an end bent in a hookform so that the first corner module upper-fastening part 1231A islocked and coupled with the upper main fastening part 1131 disposed onthe one side of the main platform 1100. The first corner moduleupper-fastening part 1231A may be provided in plural, and may beindividually provided in the first corner module wheel housings 1220A,respectively.

The first corner module lower-fastening part 1232A according to thepresent embodiment may be formed to have a form of a protrusion thatprotrudes from the outside surface of the first corner module plate1210A. More specifically, the first corner module lower-fastening part1232A is transversely extended from any one end of the front or rear ofthe first corner module plate 1210A, more specifically, an end disposedto face the end of the main platform 1100 on the one side thereof. Thefirst corner module lower-fastening part 1232A is inserted into thelower main fastening part 1132 disposed on the one side of the mainplatform 1100 as the first corner module platform 1200A comes intocontact with the main platform 1100 in the direction parallel to thelength direction of the vehicle.

The first corner module lower-fastening part 1232A may have a shapehaving an end bent in a hook form so that the first corner modulelower-fastening part 1232A is locked and coupled with the lower mainfastening part 1132. In this case, the end of the first corner modulelower-fastening part 1232A is bent in a direction opposite to adirection of the end of the first corner module upper-fastening part1231A. For example, the end of the first corner module upper-fasteningpart 1231A may be downward bent, and the end of the first corner modulelower-fastening part 1232A may be upward bent. Accordingly, when beingfastened to the main fastening part 1130, the first corner moduleupper-fastening part 1231A and the first corner module lower-fasteningpart 1232A can prevent the upper main fastening part 1131 and the lowermain fastening part 1132 from deviating in any direction thereof.

The second corner module platform 1200B includes a second corner moduleplate 1210B, a second corner module wheel housing 1220B, and the secondcorner module fastening part 1230B.

Detailed shapes of the second corner module plate 1210B and the secondcorner module wheel housing 1220B may be formed to have the same formsas the above-mentioned first corner module plate 1210A and the firstcorner module wheel housing 1220A, respectively.

The second corner module fastening part 1230B is provided in the secondcorner module plate 1210B and the second corner module wheel housing1220B, and is fastened to the main fastening part 1130 disposed on theother side of the main platform 1100. When the main platform 1100 andthe second corner module platform 1200B are assembled, the second cornermodule fastening part 1230B is disposed at a location that faces themain fastening part 1130 disposed on the other side of the main platform1100. The second corner module fastening part 1230B is locked andcoupled with the main fastening part 1130 disposed on the other side ofthe main platform 1100 as the second corner module platform 1200B comesinto contact with the main platform 1100 in the direction parallel tothe length direction of the vehicle.

The second corner module fastening part 1230B according to the presentembodiment includes the second corner module upper-fastening part 1231Band the second corner module lower-fastening part 1232B.

The second corner module upper-fastening part 1231B according to thepresent embodiment may be formed to have a form of a protrusion thatprotrudes from an outside surface of the second corner module wheelhousing 1220B. More specifically, the second corner moduleupper-fastening part 1231B is transversely extended from the end of thefront or rear of a second mounting plate 1221B, more specifically, anend disposed to face the end of the main platform 1100 on the other sidethereof. The second corner module upper-fastening part 1231B is insertedinto the upper main fastening part 1131 disposed on the one side of themain platform 1100 as the second corner module platform 1200B comes intocontact with the main platform 1100 in the direction parallel to thelength direction of the vehicle. In this case, the second corner moduleupper-fastening part 1231B may have a shape having an end bent in a hookform so that the second corner module upper-fastening part 1231B islocked and coupled with the upper main fastening part 1131 disposed onthe one side of the main platform 1100. The second corner moduleupper-fastening part 1231B may be provided in plural, and may beindividually provided in the second corner module wheel housings 1220B,respectively.

The second corner module lower-fastening part 1232B according to thepresent embodiment may be formed to have a form of a protrusion thatprotrudes from an outside surface of the second corner module plate1210B. More specifically, the second corner module lower-fastening part1232B is transversely extended from any one end of the front and rear ofthe second corner module plate 1210B, more specifically, an end disposedto face the end of the main platform 1100 on the other side thereof. Thesecond corner module lower-fastening part 1232B is inserted into thelower main fastening part 1132 disposed on the other side of the mainplatform 1100 as the first corner module platform 1200B comes intocontact with the main platform 1100 in the direction parallel to thelength direction of the vehicle.

The second corner module lower-fastening part 1232B may have a shapehaving an end bent in a hook form so that the second corner modulelower-fastening part 1232B is locked and coupled with the lower mainfastening part 1132. In this case, the end of the second corner modulelower-fastening part 1232B is bent in a direction opposite to that ofthe end of the second corner module upper-fastening part 1231B. Forexample, the end of the second corner module upper-fastening part 1231Bmay be downward bent, and the end of the second corner modulelower-fastening part 1232B may be upward bent. Accordingly, when beingfastened to the main fastening part 1130, the second corner moduleupper-fastening part 1231B and the second corner module lower-fasteningpart 1232B can prevent the upper main fastening part 1131 and the lowermain fastening part 1132 from deviating in any one direction.

The corner module 200 is supported by the frame module 100 and connectedto a wheel of the vehicle 300, and generally performs an operation, suchas driving, braking, steering, or suspension. The corner module 200 maybe provided in plural, and may be individually connected to each of thewheels 300. Each of the plurality of corner modules 200 mayindependently perform an operation, such as driving, braking, steering,or suspension, on each of the wheels 300. A detailed embodiment of thecorner module 200 is described later.

The top hat 2 is mounted on the top of the corner module apparatus 1 forthe vehicle. A boarding space for a passenger is provided within the tophat 2.

Referring to FIGS. 1 and 2 , the top hat 2 according to the presentembodiment may be formed to have a form of a box whose interior isemptied and bottom is opened. Various articles and devices suitable fora purpose of a passenger, such as a seat, a manipulation panel, and atable, may be installed within the top hat 2. The opened bottom of thetop hat 2 is disposed to face the top of the frame module 100, that is,the top of the main platform 1100, the first corner module platform1200A, and the second corner module platform 1200B. The bottom of thetop hat 2 may be coupled to the top of the main wheel housing 1120, thefirst corner module wheel housing 1220A, and the second corner modulewheel housing 1220B through bolting, and may be detachably fixed to theframe module 100. The design of the area and length of the top hat 2 maybe variously changed depending on the area, length, etc. of the framemodule 100.

The door part 3 is installed in the top hat 2 in a way to be opened andclosed, and enables a passenger to get in the top hat 2 when opened.

The door part 3 according to the present embodiment includes a firstdoor 3 a and a second door 3 b.

The first door 3 a is installed on one side of the top hat 2 in a way tobe opened and closed, and is disposed on the top of the main platform1100. Referring to FIGS. 1 and 2 , the first door 3 a according to thepresent embodiment is installed on the side of the top hat 2 in a widthdirection thereof in a way to be opened and closed. The first door 3 amay be installed on the top hat 2 in a way to be opened and closed byusing various methods, such as an open and close method and a slidingmethod. The first door 3 a may be provided in pair, and may be installedon both sides of the top hat 2, respectively, in the width directionthereof in a way to be opened and closed. Both ends of the first door 3a are disposed between the pair of main wheel housings 1120 spaced apartfrom each other in the length direction of the main plate 1110. Thebottom of the first door 3 a is disposed to face the top of the battery400 seated on the top of the main plate 1110. As the battery 400 isformed to have a lower height than the main platform 1100, the bottom ofthe first door 3 a may be disposed close to the ground, thereby inducingsmooth boarding of a passenger.

The second door 3 b is installed on the other side of the top hat 2 in away to be opened and closed, and is disposed on the top of at least oneof the first corner module platform 1200A and the second corner moduleplatform 1200B. Hereinafter, an example in which the second door 3 b isdisposed on both the tops of the first corner module platform 1200A andthe second corner module platform 1200B will be described, but thesecond door 3 b is not limited to the example. It is also possible forthe second door 3 b to be disposed on the top of any one of the firstcorner module platform 1200A and the second corner module platform1200B.

Referring to FIGS. 1 and 2 , the second door 3 b according to thepresent embodiment is provided in pair, and is installed on the sides ofthe top hat 2 in forward and backward directions in a way to be openedand closed. Accordingly, the second door 3 b may be disposed in adirection perpendicular to the first door 3 a. The second door 3 b maybe installed in the top hat 2 in a way to be opened and closed by usingvarious methods, such as an open and close method and a sliding method.Both ends of each of the pair of second doors 3 b is disposed betweenthe pair of first corner module wheel housing 1220A and second cornermodule wheel housing 1220B. The bottom of each of the pair of seconddoors 3 b is disposed to face the top of the inverter 500 seated on thetop of each of the first corner module plate 1210A and the second cornermodule plate 1210B. As the inverter 500 is formed to have a lower heightthan the first corner module platform 1200A and the second corner moduleplatform 1200B, the bottom of the second door 3 b may be disposed closeto the ground, thereby inducing smooth boarding of a passenger.

Hereinafter, a configuration of a corner module 200 according to a firstembodiment of the present disclosure is described.

FIG. 9 is a perspective view schematically illustrating a configurationof the corner module according to the first embodiment of the presentdisclosure. FIG. 10 is a perspective view illustrating a configurationof the corner module according to the first embodiment of the presentdisclosure at a view different from that of the configuration of FIG. 9. FIG. 11 is a front view schematically illustrating a configuration ofthe corner module according to the first embodiment of the presentdisclosure. FIG. 12 is a side view schematically illustrating aconfiguration of the corner module according to the first embodiment ofthe present disclosure. FIG. 13 is an exploded perspective viewschematically illustrating a configuration of the corner moduleaccording to the first embodiment of the present disclosure.

Referring to FIGS. 9 to 13 , the corner module 200 according to thefirst embodiment of the present disclosure includes a driving unit 2100,a braking unit 2200, a suspension unit 2300, and a steering unit 2400.

The driving unit 2100 rotates the wheel 300 by providing driving powerto the wheel 300.

The driving unit 2100 according to the present embodiment includes anin-wheel motor 2110 and a knuckle 2120.

The in-wheel motor 2110 is installed in the inner side of the wheel 300,and generates the driving power. The in-wheel motor 2110 according tothe present embodiment may be configured to include a stator that isfixed in the inner side of the wheel 300 and that forms a magnetic fieldby receiving a power source from the battery 400 and a rotor that isrotatably installed in the inner side of the wheel 300 and that rotatesthe wheel 300 by an electromagnetic interaction with the stator. Thestator and the rotor may have their central axis disposed on the sameline as the central axis of the wheel 300, and may be disposed in aconcentric form from the inner side of the wheel 300 in a way to bestacked with each other.

The knuckle 2120 is coupled with the in-wheel motor 2110, and provides amechanical connection to the driving unit 2100 between the braking unit2200 and the suspension unit 2300 described later. The knuckle 2120according to the present embodiment may be coupled and supported by thestator of the in-wheel motor 2110 by bolting, etc. The knuckle 2120 mayrotatably support the rotor of the in-wheel motor 2110 through themedium of a wheel bearing etc. The knuckle 2120 may be fabricated bymolding a metal-series material through casting, etc. in order to securesufficient stiffness. A detailed shape of the knuckle 2120 is notlimited to a shape illustrated in FIG. 13 . The design of the knuckle2120 may be changed in various shapes capable of supporting the in-wheelmotor 2110.

The braking unit 2200 applies or releases braking power by beinginterrupted by the rotation of the wheel 300.

The braking unit 2200 according to the present embodiment includes abrake disk 2210 and a brake caliper 2220.

The brake disk 2210 is connected to the wheel 300 or the in-wheel motor2110 and is rotated while being interlocked with the rotation of thewheel 300. The brake disk 2210 according to the present embodiment isformed to have a disc shape and installed in the inner side of the wheel300. The brake disk 2210 is disposed to have its central axis placed onthe same line as the central axis of the wheel 300. The brake disk 2210may be integratedly connected with the wheel 300 or the rotor of thein-wheel motor 2110 by bolting, etc. Accordingly, when the wheel 300 isrotated, the brake disk 2210 may be rotated by using the central axis asan axis along with the wheel 300. The design of the diameter of thebrake disk 2210 may be variously changed depending on the diameter ofthe wheel 300, the size of the in-wheel motor 2110, etc.

Upon braking of the vehicle, the brake caliper 2220 applies brakingpower by pressurizing the brake disk 2210. The brake caliper 2220according to the present embodiment may be configured to include a brakepad disposed to face the brake disk 2210, a caliper housing coupled withthe knuckle 2120 and movably supporting the brake pad, and a piston thatis movably installed in the caliper housing in a way to advance andretreat and that pressurizes the brake pad toward the brake disk 2210 orreleases the pressing of the brake pad in a moving direction thereof.

The suspension unit 2300 is connected to the driving unit 2100, andabsorbs an impact delivered from a road surface while the vehicledrives.

The suspension unit 2300 according to the present embodiment includes asuspension arm 2310 and a shock absorber module 2320.

The suspension arm 2310 is provided between the driving unit 2100 andthe steering unit 2400 described later, and supports the wheel 300. Morespecifically, the suspension arm 2310 absorbs weight applied from thewheel 300 while the vehicle drives by its own stiffness simultaneouslywith connecting the wheel 300 with the vehicle body, and plays a role inadjusting a movement of the wheel 300.

The suspension arm 2310 according to the present embodiment may includea first arm 2311 and a second arm 2312.

The first arm 2311 and the second arm 2312 have one ends rotatablyconnected to a steering body 2410 of the steering unit 2400 and theother ends rotatably connected to the knuckle 2120 of the driving unit2100. In this case, the first arm 2311 and the second arm 2312 may berotatably coupled to the steering body 2410 and the knuckle 2120 throughthe medium of a bush, a ball joint, a pin etc. The first arm 2311 andthe second arm 2312 are spaced apart from each other in up and downdirections and are disposed to face each other. The first arm 2311 andthe second arm 2312 may be formed to have a double wishbone form.Accordingly, the first arm 2311 and the second arm 2312 are able to setnegative camber of the wheel 300 to improve the cornering performance ofthe vehicle, and to set a low floor configuration that lowers the heightof the vehicle. The first arm 2311 and the second arm 2312 may beslantly disposed to form a predetermined angle. Accordingly, the firstarm 2311 and the second arm 2312 may set the length and center of a sideview swing arm (SVSA) corresponding to the type of vehicle, a drivingcondition etc. through a relative angle formed by the first arm 2311 andthe second arm 2312.

The shock absorber module 2320 is provided in a way to be retractile ina length direction thereof, and absorbs an impact or vibration deliveredfrom a road surface to the vehicle body through the wheel 300. The shockabsorber module 2320 according to the present embodiment includes acylinder 2321, a rod 2322, and an elastic body 2323.

The cylinder 2321 is extended in up and down directions and is filledwith a fluid. The bottom of the cylinder 2321 may penetrate the firstarm 2311, and the cylinder 2321 may be rotatably connected to the top ofthe second arm 2312.

The rod 2322 is extended in the length direction of the cylinder 2321.The rod 2322 has a lower side inserted into the upper end of thecylinder 2321, and is installed in a way to slidingly move in the lengthdirection of the cylinder 2321. The rod 2322 has an upper side coupledto the steering body 2410 by bolting, etc. The rod 2322 slidingly movesin the length direction of the cylinder 2321 by being interlocked bypressure of a fluid filled into the cylinder 2321

The elastic body 2323 is disposed to surround outside surfaces of thecylinder 2321 and the rod 2322. The length of the elastic body 2323 ischanged by being interlocked with a slide movement of the rod 2322. Theelastic body 2323 according to the present embodiment may be formed tohave a form of a coil spring capable of being retractile in the lengthdirection thereof. The elastic body 2323 may have both ends coupled andsupported by a lower sheet fixed to the cylinder 2321 and an upper sheetfixed to the rod 2322. The elastic body 2323 may be compressed orextended when the rod 2322 slidingly moves, may accumulate an elasticrestoring force, and may offset an impact applied from a road surface bythe accumulated elastic restoring force.

The steering unit 2400 is connected to the suspension unit 2300 and isrotatably installed on the lower side of the frame module 100. Thesteering unit 2400 is rotated clockwise or counterclockwise by using theframe module 100 as an axis, and adjusts a steering angle of the wheel300. The steering unit 2400 is installed on the lower side of the framemodule 100, and can prevent a part of the structure of the corner module200 from protruding upward from the frame module 100. Accordingly, aspatial or shape problem upon vehicle body mounting design, package, andvehicle design can be solved.

The steering unit 2400 according to the present embodiment includes thesteering body 2410 and a steering driving unit 2420.

The steering body 2410 is disposed to face the bottom of the framemodule 100, and supports the suspension unit 2300. The steering body2410 according to the present embodiment has a length direction extendedin a direction parallel to the height direction of the vehicle, and isdisposed between the frame module 100 and the suspension unit 2300. Anarea of the top of the steering body 2410 is formed to be greater thanan area of the bottom thereof. Accordingly, the steering body 2410 isformed to have an approximately “¬” cross-sectional form. The bottom ofthe steering body 2410 is coupled with one ends of the first arm 2311and the second arm 2312 through the medium of a bush, a ball joint, apin, etc., and rotatably supports the first arm 2311 and the second arm2312. The lower side of the top of the steering body 2410 is coupledwith the top of the rod 2322 by bolting, etc., and supports the shockabsorber module 2320.

An accommodation part 2411 in which the steering driving unit 2420described later is accommodated is provided in the steering body 2410.The accommodation part 2411 according to the present embodiment may beformed to have a form of a groove that is concavely recessed and formeddownward from the upper side of the top of the steering body 2410. Thedesign of a detailed cross-sectional form of the accommodation part 2411may be variously changed depending on a shape of the steering drivingunit 2420.

The steering driving unit 2420 is installed in the steering body 2410,and rotatably supports the steering body 2410 with respect to the framemodule 100. The steering driving unit 2420 is rotated by using the framemodule 100 as an axis upon steering of the vehicle, and rotates thesteering body 2410 clockwise or counterclockwise. Accordingly, asteering angle of the wheel 300 connected to the steering body 2410through the medium of the suspension unit 2300 can be adjusted.

The steering driving unit 2420 according to the present embodimentincludes a power generation module 2421, a rotation module 2422, and apower transfer module 2423.

FIG. 14 is a cross-sectional view schematically illustrating aconfiguration of the steering driving unit according to the firstembodiment of the present disclosure.

Referring to FIG. 14 , the steering driving unit 2420 according to thepresent embodiment includes a power generation module 2421, a rotationmodule 2422, and a power transfer module 2423.

The power generation module 2421 generates rotatory power by receiving apower source. The power generation module 2421 according to the firstembodiment of the present disclosure may be implemented as various typesof electric motors which convert, into rotatory power, a power sourceapplied from the outside and output the rotatory power through a drivingshaft 2421 a. The power generation module 2421 may be connected to thebattery 400 installed in the frame module 100, and may be supplied withthe power source from the battery 400.

The power generation module 2421 may be seated on one side of theaccommodation part 2411, and may be detachably fixed to the steeringbody 2410 by bolting, etc. The driving shaft 2421 a of the powergeneration module 2421 is disposed to be placed on the same axis as thecentral axis A of the power generation module 2421. The central axis Aof the power generation module 2421 may be disposed in parallel to thecentral axis B of the rotation module 2422 described later. However, thepower generation module 2421 is not limited to such an example. Thepower generation module 2421 may be disposed perpendicularly to thecentral axis B of the rotation module 2422 depending on a detailedstructure of the power transfer module 2423 described later.

The rotation module 2422 is rotated by using the frame module 100 as anaxis by being interlocked with rotatory power generated by the powergeneration module 2421. As the rotation module 2422 is rotated by usingthe frame module 100 as an axis, the rotation module 2422 adjusts asteering angle of the wheel 300 by performing an orbital motion on thepower generation module 2421 around the rotation module 2422. Such adetailed operation process of the power generation module 2421 isdescribed later.

The rotation module 2422 is seated on the other side of theaccommodation part 2411, and is disposed in a way to be spaced apartfrom the power generation module 2421. The rotation module 2422 may bedetachably fixed to the steering body 2410 by bolting, etc. The rotationmodule 2422 is connected to the power generation module 2421 through themedium of the power transfer module 2423 described later. The rotationmodule 2422 may be installed in the steering body 2410 in the state inwhich the rotation module 2422 has been integratedly accommodated in thesame case, etc. along with the power generation module 2421 and thepower transfer module 2423 as illustrated in FIG. 14 , and may beinstalled in the steering body 2410 separately from the power generationmodule 2421 and the power transfer module 2423.

The central axis B of the rotation module 2422 may be disposed on thesame plane as a central surface of the wheel 300. In this case, thecentral surface of the wheel 300 may be implemented as a plane thatbelongs to a plane through which the central axis of the wheel 300perpendicularly penetrates and that symmetrically divides the wheel 300in the width direction of the vehicle. Accordingly, the central axis ofrotation of the rotation module 2422 may coincide with an actualsteering axis of the wheel 300, thereby inducing stable steering of thewheel 300.

The rotation module 2422 according to the present embodiment includes amounting part 2422 a, a rotation module body 2422 b, an input shaft 2422c, an output shaft 2422 d, a deceleration module 2422 e, and a steeringguide 2422 f.

The mounting part 2422 a forms an upper external appearance of therotation module 2422, and is fixed to the lower side of the frame module100. The mounting part 2422 a according to the present embodiment may beformed to have a form of a plate facing parallel to the frame module100, more specifically, the first mounting plate 1221A or the secondmounting plate 1221B. The top of the mounting part 2422 a is detachablycoupled to the bottom of the first mounting plate 1221A or the secondmounting plate 1221B by bolting, etc. The mounting part 2422 a is fixedto the bottom of the frame module 100, and generally supports the cornermodule 200 with respect to the frame module 100.

The rotation module main body 2422 b forms a lower external appearanceof the rotation module 2422, and is relatively rotatably installed alongwith the mounting part 2422 a. The rotation module main body 2422 baccording to the present embodiment is formed to have a cylindricalshape having the inside emptied, and is installed on the lower side ofthe mounting part 2422 a. The top of the rotation module main body 2422b is rotatably connected to the bottom of the mounting part 2422 athrough the medium of a bearing, etc. The bottom of the rotation modulemain body 2422 b is seated on the other side of the accommodation part2411 and supported by the accommodation part 2411. The rotation modulemain body 2422 b may be assembled in a case in which the rotation modulemain body 2422 b is integratedly accommodated along with the powergeneration module 2421 and the power transfer module 2423, and may befixed to the steering body 2410. The rotation module main body 2422 bmay be directly assembled and fixed to the steering body 2410.

The input shaft 2422 c is rotatably installed within the rotation modulemain body 2422 b, and is rotated by rotatory power delivered from thepower transfer module 2423. The input shaft 2422 c according to thepresent embodiment may be formed to have a form of a shaft in which thecentral axis thereof is disposed on the same axis as the central axis Bof the rotation module 2422. The bottom of the input shaft 2422 cprotrudes downward from the rotation module main body 2422 b, and isconnected to the power transfer module 2423.

The output shaft 2422 d is rotatably supported by the mounting part 2422a. The output shaft 2422 d is rotated by being interlocked with therotation of the input shaft 2422 c, and rotates the steering body 2410by using the mounting part 2422 a as an axis. The output shaft 2422 daccording to the present embodiment may be formed to have a form of ashaft in which the central axis thereof is disposed on the same axis asthe central axis B of the rotation module 2422. The bottom of the outputshaft 2422 d is relatively rotatably connected to the top of the inputshaft 2422 c through the medium of a bearing. The top of the outputshaft 2422 d is rotatably inserted into the bottom of the mounting part2422 a by using the mounting part 2422 a as an axis. The output shaft2422 d is connected to the deceleration module 2422 e described later,and is rotated by rotatory power delivered from the deceleration module2422 e when the input shaft 2422 c is rotated.

The deceleration module 2422 e is provided between the input shaft 2422c and the output shaft 2422 d, and delivers rotatory power of the inputshaft 2422 c to the output shaft 2422 d. More specifically, thedeceleration module 2422 e amplifies the size of rotatory powerdelivered to the output shaft 2422 d by decelerating a rotation speed ofthe input shaft 2422 c at a set deceleration ratio, and rotates theoutput shaft 2422 d by outputted rotatory power. The deceleration module2422 e according to the present embodiment may be implemented as strainwave gearing including a wave generator, a flex spline, or a circularspline.

The steering guide 2422 f is extended from the rotation module main body2422 b and is connected to a measurement module 2424 described later.The steering guide 2422 f according to the present embodiment may beformed to have a disc shape having a hollow form in which an end of aninner circumference thereof is bent upward, and may be disposed betweenthe rotation module main body 2422 b and the output shaft 2422 d. Thesteering guide 2422 f has an outer circumferential surface fixed to theinner circumferential surface of the rotation module main body 2422 b,and is rotated by using the central axis thereof as an axis along withthe rotation module main body 2422 b when the rotation module main body2422 b is rotated. An end of the inner circumference of the steeringguide 2422 f is coupled to an inner diameter part 2424 a of themeasurement module 2424 described later. The steering guide 2422 frotates the inner diameter part 2424 a by being interlocked with therotation of the rotation module main body 2422 b.

The power transfer module 2423 is provided between the power generationmodule 2421 and the rotation module 2422, and delivers, to the rotationmodule 2422, rotatory power generated by the power generation module2421. The power transfer module 2423 according to the present embodimentmay be formed to have a form of a belt or chain formed to form a closedcurve. The power transfer module 2423 has both ends connected to theends of the driving shaft 2421 a of the power generation module 2421 andthe input shaft 2422 c of the rotation module 2422, respectively. Inthis case, the power transfer module 2423 can be prevented fromtwisting, etc. as the central axis A of the power generation module 2421is disposed in parallel to the central axis B of the rotation module2422. When the driving shaft 2421 a is rotated, the power transfermodule 2423 is moved in a caterpillar way and delivers rotatory power tothe input shaft 2422 c. However, the power transfer module 2423 is notlimited to such a structure. The design of the power transfer module2423 may be changed in various types of power transfer means which candeliver, to the rotation module 2422, rotatory power generated by thepower generation module 2421, such a worm or a worm wheel.

The measurement module 2424 measures a rotation angle of the rotationmodule 2422 according to the steering of the wheel 300. The measurementmodule 2424 according to the present embodiment is disposed within therotation module main body 2422 b and fixed to the bottom of the mountingpart 2422 a. The inner diameter part 2424 a capable of being rotated byusing the central axis of the measurement module 2424 as an axis isprovided in the inner circumferential surface of the measurement module2424. The inner diameter part 2424 a is connected to the steering guide2422 f and rotated along with the steering guide 2422 f when the outputshaft 2422 d is rotated. Upon steering of the vehicle, the measurementmodule 2424 measures a rotation angle of the rotation module 2422 bymeasuring an angle at which the inner diameter part 2424 a has beenrotated on the basis of an initial location of the output shaft 2422 d.A detailed form of the measurement module 2424 is not limited to anyone, and may be implemented as various types of steering angle sensorscapable of detecting a rotation angle of the output shaft 2422 d. Themeasurement module 2424 transmits data about a measured rotation angleof the rotation module 2422 to a control unit, such as the ECU of thevehicle, that is, a control unit 20 described later, so that the controlunit performs rolling control, rotation control, etc. of the vehicle.

Hereinafter, an operating process of the corner module 200 according tothe first embodiment of the present disclosure is described in detail.

FIGS. 15, 16A and 16B are operation diagrams schematically illustratingan operating process of the corner module according to the firstembodiment of the present disclosure.

When a vehicle requires rotation driving while driving, the drivingshaft 2421 a is rotated by the power generation module 2421, androtatory power is generated.

The power transfer module 2423 is moved in a caterpillar way by therotation of the driving shaft 2421 a, and delivers the rotatory power ofthe power generation module 2421 to the rotation module 2422.

The rotatory power delivered to the rotation module 2422 is delivered tothe output shaft 2422 d sequentially through the input shaft 2422 c andthe deceleration module 2422 e.

More specifically, the elliptical cam of a wave generator of thedeceleration module 2422 e is rotated by the rotatory power of the inputshaft 2422 c.

Thereafter, the flex spline is rotated while generating elasticdeformation. Accordingly, locations of the teeth of a gear on the outercircumferential surface of the flex spline partially engaged with theteeth of a gear on the inner circumferential surface of the circularspline are sequentially moved.

When the elliptical cam is rotated once, the flex spline is moved in adirection opposite to the rotation direction of the elliptical cam by adifference between the number of teeth of the gear on the outercircumferential surface of the flex spline and the number of teeth ofthe gear on the inner circumferential surface of the flex spline.

Accordingly, the output shaft 2422 d coupled with the flex spline isrotated in a direction opposite to the rotation direction of the inputshaft 2422 c at a reduced rotation speed than a rotation speed of theinput shaft 2422 c.

The output shaft 2422 d is rotated by using the mounting part 2422 afixed to the first mounting plate 1221A or the second mounting plate1221B, more specifically, the central axis B of the rotation module 2422as an axis.

As the output shaft 2422 d is rotated by using the central axis B of therotation module 2422 as an axis, the rotation module main body 2422 bintegrated with the output shaft 2422 d and the steering body 2410 arealso rotated by using the central axis B of the rotation module 2422 asan axis.

Accordingly, the power generation module 2421 spaced apart from thecentral axis B of the rotation module 2422 at a predetermined intervalperforms an orbital motion around the central axis B of the rotationmodule 2422.

Rotatory power generated as the steering body 2410 is rotated isdelivered to the wheel 300 sequentially through the suspension unit 2300and the driving unit 2100.

As the central axis B of the rotation module 2422 is disposed on thesame plane as the central surface of the wheel 300, the wheel 300 isrotated by the delivered rotatory power by using the central axis B ofthe rotation module 2422 as an axis. The wheel 300 has its steeringangle adjusted and rotates and drives the vehicle.

Hereinafter, a configuration of a vehicle including a corner moduleapparatus according to another embodiment of the present disclosure isdescribed.

In this process, a description redundant with that of the vehicleincluding the corner module apparatus according to the aforementionedembodiment of the present disclosure is omitted for convenience ofdescription.

FIG. 17 is a front view schematically illustrating a configuration of avehicle including a corner module apparatus according to anotherembodiment of the present disclosure.

Referring to FIG. 17 , a frame module 100 according to anotherembodiment of the present disclosure includes a plurality of firstcorner module platforms 1200A and a plurality of second corner modulesplatforms 1200B.

The plurality of first corner module platforms 1200A and the pluralityof second corner module platforms 1200B are extended in the lengthdirection of a vehicle body from one side and the other side of a mainplatform 1100.

More specifically, the neighboring first corner module platforms 1200Aare connected in series in the length direction of the vehicle body fromone side of the main platform 1100. The neighboring second corner moduleplatforms 1200B are connected in series in the length direction of thevehicle body from the other side of the main platform 1100. In thiscase, the numbers of plurality of first corner module platforms 1200Aand plurality of second corner module platforms 1200B may be identicaland may be different. Accordingly, the number of corner modules 200installed in the frame module 100 according to another embodiment of thepresent disclosure may be freely expanded to both sides of the mainplatform 1100 based on a purpose of a vehicle.

FIG. 18 is a diagram schematically illustrating a configuration of afirst corner module platform and a second corner module platformaccording to another embodiment of the present disclosure.

Referring to FIG. 18 , the first corner module platform 1200A and thesecond corner module platform 1200B according to the present embodimentfurther include a first corner module extension fastening part 1240A anda second corner module extension fastening part 12408, respectively.

The first corner module extension fastening part 1240A includes a firstcorner module plate 1210A and a first corner module wheel housing 1220A.The first corner module extension fastening part 1240A is disposed onthe opposite side of a first corner module fastening part 1230A in thefirst corner module platform 1200A. That is, the first corner modulefastening part 1230A and the first corner module extension fasteningpart 1240A are disposed at both ends of the first corner module platform1200A.

The first corner module extension fastening part 1240A provided in anyone first corner module platform 1200A is detachably coupled to thefirst corner module fastening part 1230A provided in a neighbor firstcorner module platform 1200A. More specifically, the first corner moduleextension fastening part 1240A is locked and coupled with the firstcorner module fastening part 1230A as neighbor first corner moduleplatforms 1200A come into contact with each other in a directionparallel to the length direction of a vehicle. Accordingly, theplurality of first corner module platforms 1200A that are extended inseries may be sequentially connected in the length direction of thevehicle.

FIGS. 19 and 20 are enlarged views schematically illustrating aconfiguration of the first corner module extension fastening part andthe second corner module extension fastening part according to anotherembodiment of the present disclosure.

Referring to FIGS. 19 and 20 , the first corner module extensionfastening part 1240A according to the present embodiment includes afirst corner module upper-extension fastening part 1241A and a firstcorner module lower-extension fastening part 1242A.

The first corner module upper-extension fastening part 1241A accordingto the present embodiment may be formed to have a form of a groove thatis concavely recessed and formed from the first corner module wheelhousing 1220A, more specifically, an outside surface of a first mountingplate 1221A. The first corner module upper-extension fastening part1241A is perpendicularly downward extended from the top of the firstcorner module wheel housing 1220A. The first corner moduleupper-extension fastening part 1241A is disposed at the end of the otherof the front or rear of the first corner module wheel housing 1220A,that is, on a side opposite to the first corner module upper-fasteningpart 1231A. The first corner module upper-extension fastening part 1241Amay have a cross-sectional form having a step form so that the firstcorner module upper-extension fastening part 1241A is locked and coupledwith a first corner module upper-fastening part 1231A provided in aneighbor first corner module platform 1200A. The first corner moduleupper-extension fastening part 1241A may be provided in plural, and maybe individually provided in the first corner module wheel housings1220A.

The first corner module lower-extension fastening part 1242A accordingto the present embodiment may be formed to have a form of a groove thatis concavely recessed and formed from an outside surface of the firstcorner module plate 1210A.

The first corner module lower-extension fastening part 1242A is extendedin a direction opposite to a direction of the first corner moduleupper-extension fastening part 1241A. More specifically, the firstcorner module lower-extension fastening part 1242A is perpendicularlyupward extended from the bottom of the first corner module plate 1210A.Accordingly, when being fastened to the first corner module fasteningparts 1230A, the first corner module upper-extension fastening part1241A and the first corner module lower-extension fastening part 1242Acan prevent the first corner module fastening part 1230A from deviatingto any one direction.

The first corner module lower-extension fastening part 1242A is disposedat the end of the other of the front or rear of the first corner moduleplate 1210A, that is, on a side opposite to the first corner modulelower-fastening part 1232A. The first corner module lower-extensionfastening part 1242A may have a cross-sectional form having a step formso that the first corner module lower-extension fastening part 1242A islocked and coupled with a first corner module lower-fastening part 1232Aprovided in a neighbor first corner module platform 1200A.

The second corner module extension fastening part 1240B is provided inthe second corner module plate 1210B and the second corner module wheelhousing 1220B. The second corner module extension fastening part 1240Bis disposed on the opposite side of a second corner module fasteningpart 1230B in the second corner module platform 1200B. That is, thesecond corner module fastening part 1230B and the second corner moduleextension fastening part 1240B are disposed at both ends of the secondcorner module platform 12008, respectively.

The second corner module extension fastening part 1240B provided in anyone second corner module platform 1200B is detachably coupled the secondcorner module fastening part 1230B provided in a neighbor second cornermodule platform 1200B. More specifically, when neighbor second cornermodule platforms 1200B are brought into contact with each other in adirection parallel to the length direction of the vehicle, the secondcorner module extension fastening part 1240B is locked and coupled withthe second corner module fastening part 1230B. Accordingly, a pluralityof second corner module platforms 1200B that are extended in series maybe sequentially connected in the length direction of the vehicle.

The second corner module extension fastening part 1240B according to thepresent embodiment includes a second corner module upper-extensionfastening part 1241B and a second corner module lower-extensionfastening part 1242B.

The second corner module upper-extension fastening part 1241B accordingto the present embodiment may be formed to have a form of a groove thatis concavely recessed and formed from the second corner module wheelhousing 1220B, more specifically, an outside surface of a secondmounting plate 1221B. The second corner module upper-extension fasteningpart 1241B is perpendicularly downward extended from the top of thesecond corner module wheel housing 1220B. The second corner moduleupper-extension fastening part 1241B is disposed at the end of the otherof the front or rear of the second corner module wheel housing 1220B,that is, on the opposite side of a second corner module upper-fasteningpart 1231B. The second corner module upper-extension fastening part1241B may have a cross-sectional form having a step form so that thesecond corner module upper-extension fastening part 1241B can be lockedand coupled with the second corner module upper-fastening part 1231Bprovided in a neighbor second corner module platform 1200B. The secondcorner module upper-extension fastening part 1241B may be provided inplural and individually provided in the second corner module wheelhousing 1220B.

The second corner module lower-extension fastening part 1242B accordingto the present embodiment may be formed to have a form of a groove thatis concavely recessed and formed from the outside surface of the secondcorner module plate 1210B.

The second corner module lower-extension fastening part 1242B isextended in a direction opposite to the direction of the second cornermodule upper-extension fastening part 1241B. More specifically, thesecond corner module lower-extension fastening part 1242B isperpendicularly upward extended from the bottom of the second cornermodule plate 1210B. Accordingly, when being fastened to the secondcorner module fastening part 1230B, the second corner moduleupper-extension fastening part 1241B and the second corner modulelower-extension fastening part 1242B can prevent the second cornermodule fastening part 1230B from deviating in any direction thereof.

The second corner module lower-extension fastening part 1242B isdisposed at the end of the other of the front or rear of the secondcorner module plate 1210B, that is, on the opposite side of the secondcorner module lower-fastening part 1232B. The second corner modulelower-extension fastening part 12428 may have a cross-sectional formhaving a step form so that the second corner module lower-extensionfastening part 12428 can be locked and coupled with the second cornermodule lower-fastening part 12328 provided in a neighbor second cornermodule platform 1200B.

A second door 3 b according to the present embodiment is provided inpair. The pair of second doors 32 b is installed on sides of the top hat2 in forward and backward directions in a way to be opened and closed.The pair of second doors 3 b may be disposed on the first corner moduleplatform 1200A and the second corner module platform 1200B disposed onthe outermost side thereof in the length direction of a vehicle body,respectively, among a plurality of first corner module platforms 1200Aand second corner module platforms 1200B.

Hereinafter, a configuration of a vehicle including a corner moduleapparatus for a vehicle according to still another embodiment of thepresent disclosure is described in detail.

In this process, a description redundant with that of a vehicleincluding a corner module apparatus for a vehicle according to theembodiment or another embodiment of the present disclosure is omittedfor convenience of description.

FIG. 21 is a front view schematically illustrating a configuration of avehicle including a corner module apparatus for a vehicle according tostill another embodiment of the present disclosure.

Referring to FIG. 21 , the vehicle including the corner module apparatusfor a vehicle according to still another embodiment of the presentdisclosure includes a main platform assembly 1000, a first corner moduleplatform 1200A, and a second corner module platform 1200B.

The main platform assembly 1000 includes a middle module platform 1300disposed between at least two main platforms 1100 and a main platform.

Neighbor main platforms 1100 are disposed to be spaced apart from eachother at a given interval in a length direction of the vehicle. In thiscase, the first corner module platform 1200A is detachably coupled toone side (a left side of FIG. 21 ) of the main platform 1100 disposed onthe outermost side of one side (the left side of FIG. 21 ) among theplurality of main platforms 1100. The second corner module platform1200A is detachably coupled to the other side (a right side of FIG. 21 )of the main platform 1100 disposed on the outermost side of the otherside (the right side of FIG. 21 ) among the plurality of main platforms1100. Accordingly, the frame module 100 according to still anotherembodiment of the present disclosure may also be applied to a vehiclehaving a vehicle body whose length is relatively long, such as a tram, abus, or a trailer, because weight of a battery 400 can be distributedthrough the plurality of main platforms 1100.

The middle module platform 1300 includes a third corner module platform1200C disposed between neighbor main platforms 1100 and supporting acorner module 200.

One or more third corner module platforms 1200C may be provided betweenneighbor main platforms 1100. If the third corner module platform 1200Cis provided in plural, the plurality of third corner module platforms1200C may be connected in series in the length direction of the vehiclebody. The third corner module platform 1200C disposed on the outermostside of the plurality of third corner module platforms 1200C isdetachably coupled to an end that belongs to the end of a neighbor mainplatform 1100 and with which the first corner module platform 1200A andthe second corner module platform 1200B are not coupled.

The third corner module platform 1200C has a bottom coupled with thecorner module 200 described later and supports the corner module 200.The corner module 200 and an inverter 500 for converting, into AC power,DC power supplied from the battery 400 and delivering the AC power tothe corner module 200 are mounted within the third corner moduleplatform 1200C.

The third corner module platform 1200C according to the presentembodiment includes a third corner module plate, a third corner modulewheel housing, and a third corner module fastening part.

Detailed shapes of the third corner module plate, the third cornermodule wheel housing, the third corner module fastening part, and thethird corner module extension fastening part may be identical with theshapes of the first corner module plate 1210A, the first corner modulewheel housing 1220A, the first corner module fastening part 1230A, andthe first corner module extension fastening part 1240A illustrated inFIG. 10 .

For the smooth coupling of the main platform 1100, the third cornermodule extension fastening part provided in the third corner moduleplatform 1200C disposed at any one end among the plurality of thirdcorner module platforms 1200C disposed between neighbor main platforms1100 may be formed to have a form of a hook that protrudes from thethird corner module plate and the third corner module wheel housing.

The top of a mounting part 2422 a provided in the plurality of cornermodules 200 according to the present embodiment may be detachablycoupled with the bottom of the first mounting plate 1221A, the secondmounting plate 1221B, or the third mounting plate by bolting, etc.depending on a location.

An opened bottom of a top hat 2 according to the present embodiment isdisposed to face the top of the frame module 100, that is, the tops ofthe main platform assembly 1000, the first corner module platform 1200A,and the second corner module platform 12008. The top hat 2 may have thebottom coupled with the tops of the main wheel housing 1120, the firstcorner module wheel housing 1220A, the second corner module wheelhousing 1220B, and the third corner module wheel housing by bolting, andmay be detachably fixed to the frame module 100.

A first door 3 a according to the present embodiment may be provided inplural. The first doors 3 a may be spaced apart from each other at agiven interval in the length direction of the top hat 2, and may beindividually disposed on the main platform 1100 provided in the mainplatform assembly 1000.

FIG. 22 is a block diagram for describing a function of a corner moduleapparatus for a vehicle according to an embodiment of the presentdisclosure. Referring to FIG. 22 , the corner module apparatus for avehicle according to an embodiment of the present disclosure includes anacquisition module 10, a controller 20, and an output unit 30.

The acquisition module 10 functions as a module for obtaining overallinformation that is necessary for the controller 20 to implement firstto fifth applications described later, and includes a steering wheelangle acquisition part 11, a lever ratio acquisition part 12, a brakinginitiation manipulation acquisition unit 13, a wheel velocityacquisition part 14, and a vehicle information acquisition unit 15 asillustrated in FIG. 22 . The steering wheel angle acquisition part 11and the lever ratio acquisition part 12 are related to the firstapplication. The braking initiation manipulation acquisition unit 13 isrelated to the second application. The wheel velocity acquisition part14 is related to the third and fourth applications. The vehicleinformation acquisition unit 15 is related to the fifth application.

The steering wheel angle acquisition part 11 may obtain a steering wheelangle. The steering wheel angle may correspond to a steering angleformed through the steering of a driver for a steering wheel or asteering angle command from an ADAS system. Accordingly, the steeringwheel angle acquisition part 11 may be implemented as a separate inputmodule for obtaining a steering angle command outputted by a steeringangle sensor or the ADAS system mounted on a vehicle.

The lever ratio acquisition part 12 may obtain the lever ratio. In thefirst application described later, the lever ratio is defined as aparameter indicating whether the front wheel and rear wheel of a bicyclemodel are inphase or reversed-phased and a steering angle ratio betweenthe front wheel and rear wheel, which are defined with respect to avehicle, and may have a value of −1 to 1. A sign of the lever ratioindicates whether the front wheel and rear wheel of the bicycle modelare inphase or reverse-phased (e.g., an inphase when the sign is apositive value, and a reverse phase when the sign has a negative value).The size of the lever ratio indicates a steering angle ratio between thefront wheel and rear wheel of the bicycle model (e.g., when the leverratio is 0.5, a front wheel steering angle: a rear wheel steeringangle=2:1). The lever ratio may be configured to be changed based on amanipulation of a driver. To this end, the lever ratio acquisition part12 may be implemented as a lever structure (an example of FIG. 23 )provided in the interior of a vehicle or a touch screen structureprovided in the instrument panel of a vehicle. Accordingly, the leverratio may be changed by a lever manipulation of a driver or a touchmanipulation of a driver on the touch screen.

The braking initiation manipulation acquisition unit 13 may obtain abraking initiation manipulation of a vehicle from a driver. In thesecond application described later, braking may correspond to a conceptincluding a braking operation (e.g., sudden braking) in the state inwhich a vehicle drives on a slope S and a braking operation (i.e.,parking braking) for maintaining a parked or stopped in a slope S.However, as described later, in the second application, an operation ofthe present embodiment may be applied when a vehicle moves in a presetlow-speed area for the posture stability of the vehicle if a brakingoperation in the state in which the vehicle drives on the slope S isperformed, in that braking is performed through a method ofindependently controlling the steering of each of the four wheels of thevehicle. The braking initiation manipulation acquisition unit 13 may beimplemented in the form of a switch separately provided within avehicle, and may obtain, as the braking initiation manipulation, amanipulation of a driver for the switch.

The wheel velocity acquisition part 14 may obtain a wheel velocity ofthe four wheels of a vehicle. The wheel velocity acquisition part 14 maybe implemented as a motor sensor for sensing the number of revolutionsof an in-wheel motor mounted on each wheel. The wheel velocityacquisition part 14 may obtain wheel velocities of a left front wheel,right front wheel, left rear wheel, and right rear wheel, respectively.

The vehicle information acquisition unit 15 may obtain driving stateinformation and driving environment information of a vehicle. Thedriving state information may include a vehicle speed and heading angleof a vehicle. The driving environment information may includesurrounding image information (e.g., a front image) of a vehicle. Inorder to obtain such driving state information and driving environmentinformation, the vehicle information acquisition unit 15 may use varioussensors (e.g., a vehicle sensor, a gyro sensor, and a camera sensor)mounted on a vehicle. Driving state information and driving environmentinformation of a vehicle obtained by the vehicle information acquisitionunit 15 may be used in a process of calculating information on adistance up to a target point, target curvature, and a target steeringangle in the fifth application described later.

The controller 20 is a main agent that independently controls thedriving and steering of the four wheels of a vehicle through individualdriving torque for each of the four wheels, and may be implemented as anelectronic control unit (ECU), a central processing unit (CPU), aprocessor, or a system on chip (SoC). The controller 20 may control aplurality of hardware or software components connected to the controller20 by driving an operating system or an application, and may performvarious data processing and operations. The controller 20 may beconfigured to execute at least one instruction stored in a memory andstore data, that is, a result of the execution, in the memory.

The output unit 30 may correspond to a display, a speaker, etc. which isinstalled in a cluster of a vehicle or at a specific location within avehicle.

Hereinafter, the first to fifth applications of the corner moduleapparatus for a vehicle and detailed operating methods thereof aredescribed chiefly based on an operation of the controller 20.

In the first application, the controller 20 may calculate first tofourth target angles of a left front wheel, right front wheel, left rearwheel, and right rear wheel, respectively, based on a steering wheelangle obtained by the steering wheel angle acquisition part 11 and alever ratio obtained by the lever ratio acquisition part 12, and mayindependently control the steering of each of the four wheels of thevehicle based on the calculated first to fourth target angles.

FIG. 23 illustrates, as a general example, a series of processes ofcalculating, by the controller 20, the first to fourth target angles.Referring to FIG. 23 , (process {circle around (1)}), first, thecontroller 20 may receive a steering wheel angle obtained by thesteering wheel angle acquisition part 11 and a lever ratio obtained bythe lever ratio acquisition part 12. (Process {circle around (2)}) Next,the controller 20 may calculate a front wheel heading angle of thebicycle model from the steering wheel angle. In this case, thecontroller 20 may calculate the front wheel heading angle by multiplyingthe steering wheel angle by a preset steering sensitivity. The steeringsensitivity may correspond to a total gear ratio (TGR) of a steeringgear ratio variable device applied to the vehicle. (Process {circlearound (3)}) When the front wheel heading angle is calculated, thecontroller 20 may calculate a rear wheel heading angle of the bicyclemodel based on the front wheel heading angle and a lever ratio obtainedby the lever ratio acquisition part 12. (Process {circle around (4)}),next, the controller 20 may expand the bicycle model to a four-wheelvehicle model and calculate first to fourth target angles of the leftfront wheel, right front wheel, left rear wheel, and right rear wheel ofthe vehicle.

Among the aforementioned processes, the process {circle around (4)}corresponding to a direct process of calculating the first to fourthtarget angles may be performed in a differentiated way based on a valueof the lever ratio obtained by the lever ratio acquisition part 12.Specifically, in the present embodiment, a steering control mode of thecontroller 20 for the steering of the four wheels may be divided into afront-wheel steering mode, a four-wheel inphase steering mode, and afour-wheel reversed-phase steering mode based on a value of the leverratio. The controller 20 may calculate the first to fourth target anglesin differentiated ways based on a value of the lever ratio and for eachsteering control mode determined based on a value of the lever ratio.Hereinafter, a process of calculating the first to fourth target anglesbased on a value of the lever ratio and a steering control mode isdescribed in detail.

First, the front-wheel steering mode corresponds to a steering controlmode when the lever ratio is 0. That is, since the lever ratio is 0,rear-wheel steering control is not performed, and only commonfront-wheel steering control is performed. In this case, the controller20 may calculate first and second target angles by applying the Ackermangeometry model to a front wheel heading angle, and may calculate thirdand fourth target angles as a neutral angle (i.e., 0°) indicative of thelongitudinal direction of the vehicle because the lever ratio is 0. FIG.24 illustrates an example in which when a front wheel heading angle is45°, first and second target angles are calculated as given values basedon the center of rotation according to the Ackerman geometry model.

Next, the four-wheel inphase steering mode corresponds to a steeringcontrol mode when the lever ratio is greater than 0 and equal to orsmaller than 1. That is, since the lever ratio is a positive value, thefront wheel and the rear wheel are independently controlled in the statein which the lever ratio is inphase. In the four-wheel inphase steeringmode, first to fourth target angles are calculated in differentiatedways “when the lever ratio is greater than 0 and smaller than 1” and“when the lever ratio is 1.”

When the lever ratio is greater than 0 and less than 1, the controller20 may calculate first and second target angles by applying the Ackermangeometry model to a front wheel heading angle. Furthermore, thecontroller 20 may calculate a rear wheel heading angle of the bicyclemodel by applying (or multiplying) the lever ratio to the front wheelheading angle, and may calculate third and fourth target angles byapplying the Ackerman geometry model to the calculated rear wheelheading angle. FIG. 25 illustrates an example in which when the leverratio is 0.5, that is, when a front wheel heading angle is 45°, first tofourth target angles are calculated as given values based on the centerof rotation according to the Ackerman geometry model.

When the lever ratio is 1, the controller 20 may calculate first tofourth target angles as front wheel heading angles. That is, when thelever ratio is 1, this means a state in which the center of rotationaccording to the Ackerman geometry model is not present, the frontwheels and the rear wheels have an inphase state, and steering anglesare identically formed. The controller 20 may calculate the first tofourth target angles as front wheel heading angles. FIG. 26 illustratesan example in which when the lever ratio is 1, that is, when a frontwheel heading angle is 45°, first to fourth target angles are calculatedas front wheel heading angles.

The four-wheel reversed-phase steering mode corresponds to a steeringcontrol mode when the lever ratio is equal to greater than −1 and lessthan 0. That is, since the lever ratio is a negative value, the frontwheels and the rear wheels are independently controlled in the state inwhich the front wheels and the rear wheels have reversed phases. In thefour-wheel reversed-phase steering mode, the center of rotationaccording to the Ackerman geometry model is always present. Accordingly,the controller 20 may calculate first and second target angles byapplying the Ackerman geometry model to a front wheel heading angle, andmay calculate third and fourth target angles by applying the Ackermangeometry model to a rear wheel heading angle of the bicycle model whichis calculated by applying the lever ratio to the front wheel headingangle. FIG. 27 illustrates an example in which when the lever ratio is−0.8, that is, when a front wheel heading angle is 45°, first to fourthtarget angles are calculated as predetermined values based on the centerof rotation according to the Ackerman geometry model. FIG. 28illustrates an example in which when the lever ratio is −1, that is,when a front wheel heading angle is 45°, first to fourth target anglesare calculated as predetermined values based on the center of rotationaccording to the Ackerman geometry model.

Table 1 below illustrates a method of calculating the first to fourthtarget angles based on a value of the lever ratio and a steering controlmode.

TABLE 1 Steering control Lever ratio mode (R) Method of calculatingtarget angle Front-wheel 0 First and second target angles: steering modeAckerman geometry model Third and fourth target angles: neutral angleFour-wheel 0 < R < 1 First to fourth target angles: Ackerman inphasesteering geometry model mode R = 1 First to fourth target angles: frontwheel heading angle Four-wheel −1 ≤ R < 0 First to fourth target angles:Ackerman reversed-phase geometry model steering mode

As described above, the lever ratio may be configured to be changed andset based on a manipulation of a driver. Accordingly, if suddentransition of a steering control mode is caused because the lever ratiois changed in a process of a vehicle driving, there occurs a problem inthat the driving stability of a vehicle, such as a slip of a vehicletire to the rollover of a vehicle, is reduced. In order to prevent sucha problem, in the present embodiment, when the transition of a steeringcontrol mode is caused due to a change in the lever ratio, thecontroller 20 may perform the transition of the steering control modeduring a preset excess time by controlling change speeds of the steeringangles of the four wheels at a preset control speed. The control speedmay be preset in the controller 20 based on experimental results of adesigner so that the control speed has a sufficiently low value within arange in which the driving stability of a vehicle is secured withoutcausing sudden transition of a steering control mode. The excess timemay also be preset in the controller 20 as a value corresponding to acontrol speed. As a detailed example, if transition to the four-wheelreversed-phase steering mode is caused because a driver changes (i.e.,is in response to changes in) the lever ratio to −0.5 in the state inwhich a vehicle drives in the four-wheel inphase steering mode, thecontroller 20 changes a current steering angle of a rear wheel to atarget angle (i.e., third and fourth target angles in the four-wheelreversed-phase steering mode), but may slowly change the steering angleof the rear wheel to the third and fourth target angles based on acontrol speed so that the driving stability of the vehicle can besecured.

FIG. 29 is a flowchart for describing an operating method in the firstapplication of the corner module apparatus for a vehicle according to anembodiment of the present disclosure. An operating method of the cornermodule apparatus for a vehicle according to the present embodiment isdescribed with reference to FIG. 29 . A detailed description of aportion redundant with the aforementioned contents is omitted, and atime-series configuration thereof is chiefly described.

First, the steering wheel angle acquisition part 11 obtains a steeringwheel angle (S10 a). The lever ratio acquisition part 12 obtains a leverratio indicating whether the front wheels and rear wheels of the bicyclemodel are inphase and reversed-phased and a steering angle ratio betweenthe front wheels and the rear wheels, which have been defined withrespect to a vehicle (S20 a). The lever ratio has a value of −1 to 1. Asign of the lever ratio indicates whether the front wheels and rearwheels of the bicycle model are inphase and reversed-phased. The size ofthe lever ratio indicates a steering angle ratio between the frontwheels and rear wheels of the bicycle model.

Next, the controller 20 calculates a front wheel heading angle of thebicycle model based on the steering wheel angle obtained in step S10 a,and calculates a rear wheel heading angle of the bicycle model based onthe calculated front wheel heading angle and the lever ratio obtained instep S20 a (S30 a). In step S30 a, the controller 20 calculates thefront wheel heading angle by multiplying the steering wheel angle by apreset steering sensitivity.

Next, the controller 20 expands the bicycle model to a four-wheelvehicle model, and calculates first to fourth target angles of a leftfront wheel, right front wheel, left rear wheel, and right rear wheel ofthe vehicle, respectively (S40 a). A method of calculating the first tofourth target angles in step S40 a is differentially determined based onthe lever ratio obtained in step S20 a. Specifically, the first tofourth target angles are calculated in differentiated ways based on avalue of the lever ratio and for each steering control mode determinedbased on a value of the lever ratio. The steering control mode includesthe front-wheel steering mode corresponding to a case where the leverratio is 0, the four-wheel inphase steering mode corresponding to a casewhere the lever ratio is greater than 0 and equal to or smaller than 1,and the four-wheel reversed-phase steering mode corresponding to a casewhere the lever ratio is equal to greater than −1 and less than 0.

When a steering control mode of the vehicle is the front-wheel steeringmode, in step S40 a, the controller 20 calculates the first and secondtarget angles by applying the Ackerman geometry model to the front wheelheading angle, and calculates the third and fourth target angles as aneutral angle indicative of the longitudinal direction of the vehicle.

When a steering control mode of the vehicle is the four-wheel inphasesteering mode or the four-wheel reversed-phase steering mode in thestate in which the lever ratio is greater than 0 and less than 1, instep S40 a, the controller 20 (i) calculates the first and second targetangles by applying the Ackerman geometry model to the front wheelheading angle and (ii) calculates a rear wheel heading angle of thebicycle model by applying the lever ratio to the front wheel headingangle and calculates the third and fourth target angles by applying theAckerman geometry model to the calculated rear wheel heading angle.

When a steering control mode of the vehicle is the four-wheel inphasesteering mode in the state in which the lever ratio is 1, in step S40 a,the controller 20 calculates the first to fourth target angles as frontwheel heading angles.

When the first to fourth target angles are calculated in step S40 a, thecontroller 20 independently controls the steering of each of the fourwheels of the vehicle based on the first to fourth target angles (S50a). If the transition of a steering control mode is caused due to achange in the lever ratio, in step S50 a, the controller 20 performs thetransition of the steering control mode during a preset excess time bycontrolling change speeds of the steering angles of the four wheels at apreset control speed.

According to the first application, there are advantages in terms ofexpandability and a degree of freedom because independent control isapplied to the steering of each of the four wheels compared to theexisting front wheel steering method or rear wheel steering method(RWS). Independent control of the four wheels can be safely performedeven in a driving state in addition to a case where a vehicle is parkedand stopped because the transition of a steering control mode isimplemented to have continuity.

In the second application, when a braking initiation manipulation isobtained by the braking initiation manipulation acquisition unit 13, thecontroller 20 may perform the braking of a vehicle by independentlycontrolling the steering of four wheels of the vehicle.

In the case of a structure in which the four wheels are independentlycontrolled, the brake of each corner module may be removed depending ona design method, and a method of performing braking through an in-wheelmotor may be applied. In this case, since control of the in-wheel motoris impossible in the state in which a power source of the vehicle hasbeen off, a new braking logic is required because braking control isimpossible. The present embodiment proposes a method of performing thebraking of a vehicle in a way to control the state in which the fourwheels of the vehicle have been aligned by independently controlling thesteering of each of the four wheels with consideration taken of thedesign expandability of devices for independently driving the fourwheels and the desire (for example, want, need, requirement, etc.) forcorresponding braking logic. The method is described in detail below. Inorder to help understanding of an embodiment, an example in which abraking operation (i.e., parking braking) for maintaining a parked orstopped state in a slope S is described.

In the present embodiment, when a braking initiation manipulation isobtained by the braking initiation manipulation acquisition unit 13 inthe state in which a vehicle has been placed in the slope S, thecontroller 20 may perform the braking of the vehicle by independentlycontrolling the steering of four wheels of the vehicle based on an angle(acute angle) (defined as a direction angle in the present embodiment)between an inclined direction of the slope S and a longitudinaldirection of the vehicle. FIG. 30 illustrates an example in which thevehicle is placed in the slope S. FIGS. 31 to 33 illustrate postures ofthe vehicle when the vehicle and the slope S are viewed from a direction“A” in FIG. 30 (FIG. 31 : the direction angle is 0°, FIG. 32 : thedirection angle is 40°, FIG. 33 : the direction angle is 80°).

In this case, the controller 20 may align the four wheels of the vehicleaccording to different rules with respect to down wheels DW disposed onthe lower side of the slope S and up wheels UW disposed on the upperside of the slope S among the four wheels. The state in which thedirection angle is 0° in FIG. 31 is described as an example. Arelatively great load is applied to the down wheels DW disposed on thelower side of the slope S and a relatively small load is applied to theup wheels UW disposed on the upper side of the slope S, on the basis ofthe inclined direction of the slope S. Accordingly, aligning the downwheels DW to which the relatively great load is applied in a way tolimit a movement of the vehicle to the inclined direction of the slope Sand aligning the up wheels UW to which the relatively small load isapplied in a way to limit a movement of the vehicle to a directionperpendicular to the slope direction are effective in prohibiting amovement of the vehicle from the slope S to the longitudinal directionand transverse direction of the vehicle and maintaining the parking andstopping state of the vehicle.

Accordingly, if steering control rules for a down wheel DW and an upwheel UW are indicated as a first rule and a second rule, respectively,the first rule may be predefined in the controller 20 as a rule forlimiting a movement of the vehicle to an inclined direction of the slopeS. Furthermore, the second rule may be predefined in the controller 20as a rule for limiting a movement of the vehicle to a directionperpendicular to a slope direction of the slope S on the inclined planeof the slope.

A process of aligning down wheels DW and up wheels UW according to thefirst rule and the second rule is described in detail with reference toFIG. 34 illustrating an example in which the direction angle is 0°. Whenthe direction angle is 0°, down wheels DW are defined as two wheelsdisposed on the lower side of the slope S among the four wheels. Upwheels UW are defined as the remaining two wheels disposed on the upperside of the slope S among the four wheels (the down wheels DW and the upwheels UW are differently defined depending on the direction angle, andis described in detail later).

As a criterion for aligning down wheels DW and up wheels UW, the presentembodiment adopts a reference point that is defined as a point separatedfrom the center of gravity (GC) of a vehicle by a set distance in adirection opposite to a slope direction. If a circle having thereference point as a center thereof and passing through the center ofgravity (GC) of the vehicle is defined as a parking circle, thereference point may be named the center of parking circle (CPC). Wheelsmay be aligned on the basis of the reference point CPC, and the vehiclemay converge on a stable state with respect to the slope S. The setdistance may be represented as N*WB. In this case, WB is a distancebetween a front wheel axle and a rear wheel axle, and N corresponds to avalue that is set based on a gradient of the vehicle (e.g., thecontroller 20 may set a value of N so that N has a higher value as thegradient becomes greater. In FIGS. 34 to 36 , N=1.5). An algorithm thatdefines the reference point CPC may be preset in the controller 20.

If the reference point CPC is defined as described above, the first rulemay be defined as a rule for aligning down wheels DW so that a straightline that connects the reference point CPC and a center point of thedown wheels DW and long axes of the down wheels DW become perpendicularto each other. The second rule may be defined as a rule for aligning upwheels UW so that a straight line that connects the reference point CPCand a center point of the up wheels UW and long axes of the up wheels UWare placed on the same line.

Accordingly, as illustrated in FIG. 34 , the controller 20 may aligndown wheels DW so that a straight line that connects the reference pointCPC and a center point of the down wheels DW and long axes of the downwheels DW become perpendicular to each other according to the firstrule, and may align up wheels UW so that a straight line that connectsthe reference point CPC and a center point of the up wheels UW and longaxes of the up wheels UW are placed on the same line according to thesecond rule.

A case where down wheels DW correspond to two wheels disposed on thelower side of the slope S among the four wheels and up wheels UWcorrespond to the remaining two wheels disposed on the upper side of theslope S among the four wheels has been described. However, as describedabove, in the present embodiment, down wheels DW and up wheels UW may bedifferently defined depending on a direction angle. As described above,a first area to a third area are defined.

-   -   The first area: an area in which the direction angle is equal to        or greater than 0° and less than a first reference angle    -   The second area: an area in which the direction angle is equal        to or greater than the first reference angle and less than a        second reference angle    -   The third area: an area in which the direction angle is equal to        or greater than the second reference angle or equal to or        smaller than 90°

The first reference angle and the second reference angle may be presetin the controller 20 based on specifications of a vehicle andexperimental results of a designer. For example, the first referenceangle may be set to 20°, and the second reference angle may be set to70°.

Accordingly, if the direction angle is present in the first area or thethird area, down wheels DW may be defined as two wheels disposed on thelower side of the slope S among the four wheels, and up wheels UW may bedefined as the remaining two wheels disposed on the upper side of theslope S among the four wheels. Furthermore, if the direction angle ispresent in the second area, down wheels DW may be defined as threewheels disposed on the lower side of the slope S among the four wheels,and up wheel UW may be defined as the remaining one wheel disposed onthe upper side of the slope S. A case where the direction angle ispresent in the first area has been described with reference to FIG. 34 .Accordingly, cases where the direction angle is present in the secondarea and the third area are described.

FIGS. 32 and 35 illustrate examples of a case where the direction angleis 40° and present in the second area. The controller 20 may align downwheels DW so that a straight line that connects the reference point CPCand a center point of down wheels DW (i.e., three down wheels DW) andlong axes of the down wheels DW become perpendicular to each otheraccording to the first rule. Furthermore, the controller 20 may align upwheels UW so that a straight line that connects the reference point CPCand a center point of an up wheel UW (i.e., the remaining one up wheelUW) and long axes of the up wheels UW are placed on the same lineaccording to the second rule.

FIGS. 33 and 36 illustrate examples of a case where the direction angleis 80° and present in the third area. The controller 20 may align downwheels DW so that a straight line that connects the reference point CPCand a center point of down wheels DW (i.e., two down wheels DW) and thelong axes of the down wheels DW become perpendicular to each otheraccording to the first rule. Furthermore, the controller 20 may align upwheels UW so that a straight line that connects the reference point CPCand a center point of up wheels UW (i.e., the remaining two up wheelsUW) and long axes of the up wheels UW are placed on the same lineaccording to the second rule.

Through such control of the steering of each wheel and braking throughalignment, a movement of a vehicle to a longitudinal direction andtransverse direction of the vehicle in the slope S can be prohibited,and a parking and stopping state can be effectively maintained.

FIG. 37 is a flowchart for describing an operating method in the secondapplication of the corner module apparatus for a vehicle according to anembodiment of the present disclosure. An operating method of the cornermodule apparatus for a vehicle according to the present embodiment isdescribed with reference FIG. 37 . A detailed description of a portionredundant with the aforementioned contents is omitted, and a time-seriesconfiguration thereof is chiefly described.

First, the controller 20 determines whether a braking initiationmanipulation of a vehicle by a driver has been obtained through thebraking initiation manipulation acquisition unit 13 (S10 b).

Next, when the braking initiation manipulation is obtained in the statein which the vehicle has been placed in the slope S, the controller 20performs the braking of the vehicle by independently controlling thesteering of four wheels of the vehicle based on a direction angle thatis defined as an angle between an inclined direction of the slope S anda longitudinal direction of the vehicle (S20 b).

In step S20 b, the controller 20 aligns the four wheels of the vehicleaccording to the first rule and the second rule with respect to downwheels DW disposed on the lower side of the slope S and up wheels UWdisposed on the upper side of the slope S among the four wheels of thevehicle. In this case, the down wheel DW and the up wheel UW may bedefined based on the direction angle. Specifically, when the directionangle is present in the first area or the third area, the down wheels DWmay be defined as two wheels disposed on the lower side of the slope Samong the four wheels of the vehicle, and the up wheels UW may bedefined as the remaining two wheels disposed on the upper side of theslope S among the four wheels of the vehicle. Furthermore, when thedirection angle is present in the second area, the down wheels DW may bedefined as three wheels disposed on the lower side of the slope S amongthe four wheels of the vehicle, and the up wheel UW may be defined asthe remaining one wheel disposed on the upper side of the slope S amongthe four wheels of the vehicle.

The aforementioned first rule is a rule for limiting a movement of avehicle to a slope direction. Furthermore, the second rule is a rule forlimiting a movement of a vehicle to a direction perpendicular to a slopedirection on an inclined plane of the slope S. The first rule and thesecond rule may be predefined in the controller 20. Specifically, if apoint isolated from the center of gravity (GC) of the vehicle by a setdistance in a direction opposite to the slope direction is defined asthe reference point CPC, the first rule is defined as a rule foraligning down wheels DW so that a straight line that connects thereference point CPC and a center point of down wheels DW, and long axesof the down wheels DW become perpendicular to each other. The secondrule is defined as a rule for aligning up wheels UW so that a straightline that connects the reference point CPC and a center point of upwheels UW and long axes of the up wheels UW are placed on the same line.Accordingly, in step S20, the controller 20 aligns down wheels DW sothat a straight line that connects the reference point CPC and a centerpoint of down wheels DW and long axes of the down wheels DW becomeperpendicular to each other according to the first rule, and aligns upwheels UW so that a straight line that connects the reference point CPCand a center point of up wheels UW and long axes of the up wheels UW areplaced on the same line according to the second rule.

According to the second application, the braking of a vehicle can besafely performed regardless of the on and off state of a power source ofthe vehicle because the braking of the vehicle is performed in a way tocontrol the state in which the four wheels of the vehicle have beenaligned by independently controlling the steering of each of the fourwheels.

In the case of the existing vehicle having an internal combustion enginestructure, driving power is delivered through an engine-driveshaft-differential-axial shaft. In contrast, in the case of a four-wheelindependent-driving method premised by the present embodiment, a speeddifference may occur between the four wheels because the four wheels areindividually and independently driven and an axial shaft is not present.Such a speed difference between the four wheels becomes a danger elementthat causes the spin or rollover of a vehicle when the vehicle drivesstraight ahead. Accordingly, the third application proposes a method ofimproving straight driving performance of a vehicle through an approachin terms of driving control, not in terms of mechanical or additionalsteering control of a vehicle.

To this end, the controller 20 may detect an abnormal wheel that causesthe deterioration of straight driving performance of a vehicle based onthe four wheel velocities obtained by the wheel velocity acquisitionpart 14, may calculate a compensation parameter for compensating for adeviation between the wheel velocities based on a wheel velocity of thedetected abnormal wheel, may determine target driving torque for drivingthe abnormal wheel based on the calculated compensation parameter, andmay control the driving of the abnormal wheel based on the determinedtarget driving torque. Hereinafter, a configuration of the presentembodiment is described in detail for each operation of the controller20.

First, in relation to the method of detecting an abnormal wheel, thecontroller 20 may detect an abnormal wheel in a way to calculate a firstaverage value of the four wheel velocities and determining whether anerror between the calculated first average value and each of the fourwheel velocities is equal to or greater than a preset threshold value.If wheel velocities of a left front wheel, right front wheel, left rearwheel, and right rear wheel are V_(fl), V_(fr), V_(rl), and V_(rr), afirst average value V_(avg) may be represented as(V_(fl)+V_(fr)+V_(rl)+V_(rr))/4. A method of detecting an abnormal wheelmay be represented as a conditional expression “V_(avg)−V_(i)≥thresholdvalue, i=fl, fr, rl, rr.” For example, if a wheel that satisfies theconditional expression corresponds to the left front wheel (fl), anabnormal wheel may be specified as the left front wheel. If a wheel thatsatisfies the conditional expression corresponds is plural, an abnormalwheel may be specified as a wheel having a lower wheel velocity amongthe plurality of wheels. Accordingly, an abnormal wheel is specified asa wheel that deteriorates straight driving performance of a vehiclebecause the abnormal wheel has a lower wheel velocity by a predeterminedvalue or more than other wheels when a vehicle drives straight ahead. Inthe conditional expression, the threshold value may be defined asanother value based on the first average value. For example, by definingthat the threshold value has a higher value as the first average valuehas a higher value, an abnormal wheel may be determined based on a morereinforced criterion for the driving stability of a vehicle in ahigh-speed area.

When detecting an abnormal wheel, the controller 20 may calculate acompensation parameter for compensating for a deviation between thewheel velocities based on a wheel velocity of the detected abnormalwheel. Compensating for a deviation between the wheel velocities meansthat a deviation between the wheel velocities of the abnormal wheel andanother wheel is reduced by increasing and compensating for drivingtorque of the abnormal wheel (i.e., by increasing the wheel velocity ofthe abnormal wheel).

In this case, the controller 20 may calculate a second average value ofwheel velocities of three wheels except the abnormal wheel, and maycalculate a compensation parameter by using, as factors, a differencevalue between the calculated second average value and the wheel velocityof the abnormal wheel and a variable gain according to the secondaverage value. In the example in which an abnormal wheel is detected asthe left front wheel, the second average value V_(target) may berepresented as (V_(fr)+V_(rl)+V_(rr))/3, and the compensation parametermay be represented as α*V_(target)*(V_(target)−V_(fl)). In the equationof the compensation parameter, the second term V_(target) functions as aterm for taking into consideration a target wheel velocity that is thesubject of tracking in the process of calculating the compensationparameter, and the third term V_(target)−V_(fl) functions as a term fortaking into consideration a deviation between the wheel velocity of theabnormal wheel and a target wheel velocity in the process of calculatingthe compensation parameter. The first term α is a variable gain, andfunctions as a scaling factor for scaling the size of the compensationparameter.

As illustrated in FIG. 38 , the variable gain may be determined as avalue that is decreased as the second average value is increased whenthe second average value (V_(target)) is placed in a predefined middleand low-speed area (e.g., an area having a predefined threshold velocity(V_(th)) or less), and may be determined as a predefined fixed when thesecond average value (V_(target)) is placed in a predefined high-speedarea (e.g., an area having more than the predefined threshold velocity(V_(th))). That is, as the second average value V_(target) functioningas a target wheel velocity has a higher value, the compensationparameter functioning as compensation for driving torque of an abnormalwheel is calculated as a lower value. In this case, it is suitable tosecure the driving stability of a vehicle without a sudden change in acurrent driving control state of the vehicle. If the second averagevalue V_(target) is greater than the threshold velocity, it is suitableto maintain the driving stability of the vehicle in calculating thecompensation parameter as a lower limit value (i.e., the fixed value).Accordingly, the controller 20 may calculate the compensation parameterso that the compensation parameter has a different value based on thesecond average value as illustrated in FIG. 38 .

When calculating the compensation parameter, the controller 20 maydetermine target driving torque for driving the abnormal wheel based onthe calculated compensation parameter. In this case, the controller 20may determine the target driving torque by applying current drivingtorque (i.e., the existing driving torque) for driving the abnormalwheel to the compensation parameter (i.e., target driving torque=currentdriving torque*compensation parameter). Thereafter, the controller 20may control the driving of the abnormal wheel based on the targetdriving torque determined as described above. Since the driving torquefor driving the abnormal wheel is compensated for compared to aconventional technology, straight driving performance of the vehicle canbe improved.

The controller 20 may recalculate a first average value of the fourwheel velocities in the state in which the driving of the abnormal wheelis controlled based on the target driving torque, and may output alarmthrough the output unit 30 when an error between the recalculated firstaverage value and a wheel velocity of the abnormal wheel is equal to orgreater than the threshold value. That is, the controller 20 maydetermine whether straight driving performance of the vehicle has beenimproved in a way to determine whether an error between the recalculatedfirst average value and the wheel velocity of the abnormal wheel is lessthan the threshold value, and may calculate target driving torquethrough the aforementioned process. Even though the driving of theabnormal wheel has been controlled, if it is determined that the errorbetween the recalculated first average value and the wheel velocity ofthe abnormal wheel is equal to or greater than the threshold value, sucha situation is a situation in which a danger element, such as the spinor rollover of the vehicle, is present because a deviation between thewheel velocities of the four wheels is equal to or greater than apredetermined value. Accordingly, the controller 20 may output alarmthrough the output unit 30 so that a driver can recognize thecorresponding situation.

FIG. 39 is a flowchart for describing an operating method in the thirdapplication of the corner module apparatus for a vehicle according to anembodiment of the present disclosure. The operating method of the cornermodule apparatus for a vehicle according to the present embodiment isdescribed with reference to FIG. 39 . A detailed description of aportion redundant with the aforementioned contents is omitted, and atime-series configuration thereof is chiefly described.

First, the controller 20 obtains four wheel velocities of a vehiclethrough the wheel velocity acquisition part 14 (S10 c).

Next, the controller 20 detects an abnormal wheel that causes thedeterioration of straight driving performance of the vehicle based onthe four wheel velocities obtained in step S10 c (S20 c). In step S20 c,the controller 20 calculates a first average value of the four wheelvelocities, and detects an abnormal wheel in a way to determine whetheran error between the calculated first average value and each of the fourwheel velocities is equal to or greater than a preset threshold value.

Next, the controller 20 calculates a compensation parameter forcompensating for a deviation between the four wheel velocities based ona wheel velocity of the abnormal wheel detected in step S20 c (S30 c).In step S30 c, the controller 20 calculates a second average value ofwheel velocities of three wheels except the abnormal wheel, andcalculates the compensation parameter by using, as factors, a differencevalue between the calculated second average value and the wheel velocityof the abnormal wheel, a variable gain according to the second averagevalue, and the second average value. The variable gain is determined asa value that is decreased as the second average value is increased whenthe second average value is placed in a predefined middle and low-speedarea, and is determined as a predefined fixed value when the secondaverage value is placed in a predefined high-speed area.

Next, the controller 20 determines target driving torque for driving theabnormal wheel based on the compensation parameter calculated in stepS30 c (S40 c). Specifically, the controller 20 determines the targetdriving torque by applying the compensation parameter to current drivingtorque for driving the abnormal wheel.

Next, the controller 20 controls the driving of the abnormal wheel basedon the target driving torque determined in step in S40 c (S50 c), andcontrols other wheels except the abnormal wheel based on the existingdriving torque.

Next, the controller 20 recalculates a first average value of the fourwheel velocities, and compares an error between the recalculated firstaverage value and a wheel velocity of the abnormal wheel with thethreshold value (S60 c). When determining that the error between therecalculated first average value and the wheel velocity of the abnormalwheel is equal to or greater than the threshold value in step S60 c, thecontroller 20 outputs alarm through the output unit 30 (S70 c).

According to the third application, straight driving performance of thevehicle can be improved by compensating for a deviation between wheelvelocities through only control of driving torque for four wheelswithout additional instrument to additional steering control for avehicle.

In the case of the existing front wheel driving vehicle, there is alimit in that battery consumption of a vehicle is increased becauseposture control over the vehicle is performed through electronic controlsystems, such as an anti-lock brake system (ABS), an electronicstability program (ESP), and electronic controlled suspension (ECS). Inthe present embodiment, posture control over a vehicle is possible in away to control the driving and steering of each wheel compared to aconventional posture control over system of a vehicle because thedriving of each wheel is independently controlled by applying the fourwheel-independent driving method. Hereinafter, a detailed configurationfor performing posture control over a vehicle in a way to control thedriving and steering of each wheel is described on the basis of anoperation of the controller 20.

In the fourth application, the controller 20 may determine whether apredefined slip condition has been satisfied based on a wheel velocityof each wheel obtained by the wheel velocity acquisition part 14, andmay perform posture control over a vehicle through driving torquecontrol for controlling driving torque of each wheel when determiningthat the slip condition has been satisfied.

The slip condition is a case where a slip has occurred in a wheel, andcorresponds to a condition for determining whether posture control forthe driving stability of a vehicle is required. In this case, thecontroller 20 may calculate a slip rate of each wheel based on a wheelvelocity of each wheel (as noted, the slip rate of each wheel may becalculated as a ratio of “a difference between a vehicle speed and eachwheel velocity” and “a vehicle speed”), may determine a maximum sliprate having a maximum value among the calculated slip rates of thewheels, and may determine that the slip condition has been satisfiedwhen the determined maximum slip rate is equal to or greater than apreset threshold value.

If it is determined that the slip condition has been satisfied, thecontroller 20 may perform posture control over the vehicle through theaforementioned driving torque control. In this case, the controller 20may control the driving of each wheel based on target driving torquehaving a lower value compared to current driving torque of each wheel(the target driving torque may be determined as a value lower than aminimum value among values of current driving torque of the four wheelsnow applied for the driving of the wheels). That is, the controller 20may perform control for reducing driving torque of the wheels in orderto solve the slip state of a current wheel, and may control the drivingof each wheel based on the same target driving torque. In this case, inorder to solve the corresponding slip state, it is necessary to decreasethe driving torque of each wheel to a lower value as a maximum slip rateis greater. Accordingly, the target driving torque may be determined tohave a lower value as the maximum slip rate has a higher value. Forexample, the target driving torque and the maximum slip rate may bedefined to have a negative linear relation in the controller 20.

After performing the driving torque control, the controller 20 maydetermine whether the slip state has been solved through driving torquecontrol by re-determining whether the slip condition has been satisfied.If it is determined that the state in which the slip condition has beensatisfied is maintained (i.e., if the slip state has not been solved),the controller 20 may perform posture control over the vehicle bysubsequently performing steering control for controlling the steering ofeach wheel.

When performing the steering control, the controller 20 may perform thesteering control in a way to displace the steering of two wheels on theopposite side of the transverse direction of a wheel having a maximumslip rate by a target steering angle. For example, if a wheel having amaximum slip rate corresponds to a right front wheel, the controller 20may perform steering control in a way to displace the steering of a leftfront wheel and a left rear wheel by a target steering angle. In theabove example, the steering control over the left front wheel and theleft rear wheel is for solving the slip state of the right front wheelby deriving the braking effect of the vehicle, and a correspondingsteering direction may be any one the left or the right. In this case,in order to solve the corresponding slip state, it is necessary to formgreater steering angles of the two wheels on the opposite side of thetransverse direction of the wheel as the maximum slip rate becomesgreater. Accordingly, the target steering angle may be determined tohave a higher value as the maximum slip rate has a higher value. Forexample, the target steering angle and the maximum slip rate may bedefined to have a positive linear relation in the controller 20. Inorder to prevent a phenomenon in which a behavior of the vehicle becomesunstable due to sudden steering control over the two wheels on theopposite side of the transverse direction of the wheel, a control timeuntil the steering angles of the two wheels on the opposite side of thetransverse direction reach the target steering angle may be set as asufficiently set time based on experimental results of a designer, andmay be set in the controller 20.

FIG. 40 is a flowchart for describing an operating method in the fourthapplication of the corner module apparatus for a vehicle according to anembodiment of the present disclosure. The operating method of the cornermodule apparatus for a vehicle according to the present embodiment isdescribed with reference to FIG. 40 . A detailed description of aportion redundant with the aforementioned contents is omitted, and atime-series configuration thereof is chiefly described.

First, the controller 20 obtains a wheel velocity of each of four wheelsof a vehicle through the wheel velocity acquisition part 14 (S10 d).

Next, the controller 20 determines whether a predefined slip conditionhas been satisfied based on the wheel velocity of each wheel obtained instep S10 d (S20 d). In step S20 d, the controller 20 calculates a sliprate of each wheel based on the wheel velocity of each wheel, determinesa maximum slip rate having a maximum value among the calculated sliprates of the four wheels, and determines that the slip condition hasbeen satisfied when the determined maximum slip rate is equal to orgreater than the preset threshold value.

If it is determined that the slip condition has been satisfied in stepS20 d, the controller 20 performs posture control over the vehiclethrough driving torque control for controlling driving torque of eachwheel (S30 d). In step S30 d, the controller 20 controls the driving ofeach wheel based on target driving torque having a lower value comparedto current driving torque of each wheel. In this case, the targetdriving torque may be determined to have a lower value as the maximumslip rate has a higher value.

After step S30 d, the controller 20 re-determines whether the slipcondition has been satisfied (S40 d).

If it is determined that the state in which the slip condition has beensatisfied is maintained in step S40 d, the controller 20 performsposture control over the vehicle through steering control forcontrolling the steering of each wheel (S50 d). In step S50 d, thecontroller 20 displaces the steering of two wheels on the opposite sideof the transverse direction of a wheel having the maximum slip rate by atarget steering angle. In this case, the target steering angle may bedetermined to have a higher value as the maximum slip rate has a highervalue.

Steps S40 d and S50 d may be repeatedly performed within a predefinedrepetition number until it is determined that the slip condition has notbeen satisfied in step S40 d (i.e., until the slip state is solved).

According to the fourth application, dependency on a conventionalposture control system of a vehicle can be removed, and posture controlover a vehicle is possible by using only a method of controlling thedriving and steering of each wheel. Accordingly, there is an effect inthat an available battery capacity can be increased by reducing batteryconsumption required for posture control over a vehicle.

In the case of the four wheel-independent driving method, the steeringof each wheel may be desired to be independently controlled because thefour wheels are not mechanically connected. In particular, in order tosecure the driving stability of a vehicle upon rotation driving, aquantitative control mechanism for steering control over each wheel maybe desired to be provided. Accordingly, the fifth application proposes amethod of independently controlling the steering of each of four wheelsof a vehicle by differentially calculating a target steering angle ofeach wheel, if the vehicle to which the four wheel-independent drivingmethod has been applied rotates and drives on a crossroad having apredetermined curvature (specifically, when the slip of each wheel doesnot occur, which corresponds to a case where the vehicle rotates at alow speed at a vehicle speed less than a set speed).

In the fifth application, the controller 20 may calculate information ona distance up to a target point, that is, a target of a movement of avehicle, based on driving state information and driving environmentinformation obtained by the vehicle information acquisition unit 15, maycalculate, based on the calculated information on the distance, targetcurvature defined as curvature of a target trajectory up to the targetpoint, may calculate a target steering angle of each of four wheels of avehicle based on the calculated target curvature, and may independentlycontrol the steering of each of the four wheels based on the targetsteering angles. Hereinafter, a configuration of the present embodimentis described in detail for each operation of the controller 20.

First, in relation to a method of calculating the information on thedistance up to the target point, the controller 20 may calculate theinformation on the distance up to the target point by using a vehiclespeed of the vehicle, an offset distance of the vehicle from the middle({circle around (4)} in FIG. 41 ) of a carriageway calculated fromsurrounding image information, and a curvature radius of the carriagewaybased on the middle of the carriageway (the offset distance and thecurvature radius of the carriageway may be calculated by analyzing alane and the carriageway included in the surrounding image information).The information on the distance may include a straight-line distance, alongitudinal distance, and a transverse distance from a current location(C in FIG. 41 ) of the vehicle to the target point (A in FIG. 41 ).

Specifically, the controller 20 may calculate the straight-line distanceup to the target point in a way to apply the vehicle speed of thevehicle to a predefined distance calculation algorithm. In this case,the distance calculation algorithm may be predefined in the controller20 as an algorithm for calculating a greater straight-line distance as avehicle speed becomes higher. For example, the distance calculationalgorithm may be defined in a linear expression form of L=A*V_(x)+B (Lis the straight-line distance, V_(x) is the vehicle speed, and A and Bare constant values designed based on experimental results of adesigner).

When calculating the straight-line distance up to the target point, thecontroller 20 may calculate a longitudinal distance and transversedistance up to the target point by using the offset distance, a headingangle of the vehicle, the curvature radius of the carriageway, and thestraight-line distance up to the target point. Referring to FIG. 41 ,Equation 1 below may be derived.

$\begin{matrix}{R^{2} = {\left( {R - y - \varepsilon} \right)^{2} + {x^{2}\left( {x^{2} = {L^{2} - y^{2}}} \right)}}} & \left\lbrack {{Equation}1} \right\rbrack\end{matrix}$  ⇒ R² = R² + y² + ε² − 2Ry + 2yε − 2εR + L² − y² ⇒ 2y(R − ε) = ε² − 2εR + L²$\left. \Rightarrow y \right. = {\frac{L^{2} + \varepsilon^{2} - {2\varepsilon R}}{2\left( {R - \varepsilon} \right)} = \frac{{\rho_{k}\left( {L^{2} + \varepsilon^{2}} \right)} - {2\varepsilon}}{2\left( {1 - {\rho\text{?}}} \right)}}$$\left. \Rightarrow y \right. = {\frac{L^{2} - \varepsilon^{2} - {2{\varepsilon\left( {R - \varepsilon} \right)}}}{2\left( {R - \varepsilon} \right)} = {\frac{\rho\text{?}\left( {L^{2} - \varepsilon^{2}} \right)}{2\left( {1 - {\rho\text{?}}} \right)}\text{?}}}$?indicates text missing or illegible when filed

Equation 2 below is obtained by arranging Equation 1 with respect to xand y.

$\begin{matrix}{x = \sqrt{L^{2} - y^{2}}} & \left\lbrack {{Equation}2} \right\rbrack\end{matrix}$${\text{?}y} = {\frac{{\rho\text{?}\left( {L^{2} + \varepsilon^{2}} \right)} - {2\varepsilon}}{2\left( {1 - {\rho\text{?}}} \right)} = {\frac{\rho\text{?}\left( {L^{2} - \varepsilon^{2}} \right)}{2\left( {1 - {\rho\text{?}}} \right)}\text{?}}}$?indicates text missing or illegible when filed

In Equations 1 and 2, L, x, and y are the straight-line distance, thelongitudinal distance, and the transverse distance up to the targetpoint, respectively. R is the curvature radius of the carriageway. ρ_(k)is curvature (1/R) of the carriageway. ϵ is the offset distance.

When calculating the information on the distance up to the target pointas described above, the controller 20 may calculate target curvaturedefined as curvature of a target trajectory up to the target point,based on the calculated information on the distance. In the presentembodiment, the target curvature may be divided into center targetcurvature defined as curvature of a target trajectory based on thecenter of the vehicle (i.e., a moving target trajectory of the center ofthe vehicle, {circle around (1)} in FIGS. 41 and 42 ), left targetcurvature defined as curvature of a target trajectory based on a leftwheel of the vehicle (i.e., a moving target trajectory of the left wheelof the vehicle, {circle around (2)} in FIG. 42 ), and right targetcurvature defined as curvature of a target trajectory based on a rightwheel of the vehicle (i.e., a moving target trajectory of the rightwheel of the vehicle, {circle around (3)} in FIG. 42 ). Afterpreferentially calculating the center target curvature, the controller20 may expand the center target curvature to the left target curvatureand the right target curvature by using wheel track information of thevehicle.

Referring to FIGS. 41 and 42 , the center target curvature may becalculated according to Equation 3 below.

$\begin{matrix}{{R_{c}{\cos\left( {\text{?} + \alpha} \right)}} = {{\frac{R\text{?}}{L}\left( {{y\cos\text{?}} - {x\sin\text{?}}} \right)} = \frac{L}{2}}} & \left\lbrack {{Equation}3} \right\rbrack\end{matrix}$$\rho_{c} = {\frac{1}{R_{c}} = {\frac{2}{L^{2}}\left( {{y\cos\text{?}} - {x\sin\text{?}}} \right)}}$?indicates text missing or illegible when filed

In Equation 3, R_(c) is the curvature radius of the moving targettrajectory of the center of the vehicle, φ is the heading angle of thevehicle, α is an angle formed by the vehicle and the target point, L isthe straight-line distance up to the target point, and ρ_(c) is thecenter target curvature (1/R_(c)).

After calculating the center target curvature, the controller 20 maycalculate the left target curvature and the right target curvature basedon the center target curvature by using the wheel track information ofthe vehicle. Referring to FIG. 42 illustrating an example in which thevehicle rotates and drives to the left, the left target curvature andthe right target curvature may be calculated according to Equations 4and 5 below, respectively.

$\begin{matrix}{{R\text{?}} = {R_{C} - w_{L}}} & \left\lbrack {{Equation}4} \right\rbrack\end{matrix}$$\rho_{L} = {\frac{1}{R_{L}} = {\frac{1}{R_{C} - w_{L}} = \frac{\rho_{c}}{1 - {\rho_{c}w_{L}}}}}$$\begin{matrix}{{R\text{?}} = {R_{C} + {w\text{?}}}} & \left\lbrack {{Equation}5} \right\rbrack\end{matrix}$${\rho\text{?}} = {\frac{1}{R_{R}} = {\frac{1}{R_{C} + w_{R}} = \frac{\rho_{c}}{1 + {\rho_{c}w_{R}}}}}$?indicates text missing or illegible when filed

In Equation 4, R_(L) is a curvature radius of a moving target trajectoryof a left wheel of the vehicle, R_(C) is a curvature radius of a movingtarget trajectory of the center of the vehicle, w_(L) is a half value ofa wheel track of the vehicle (w/2, w is the wheel track), and ρ_(L) isthe left target curvature. In Equation 5, R_(R) is a curvature radius ofa moving target trajectory of a right wheel of the vehicle, R_(C) is thecurvature radius of the moving target trajectory of the center of thevehicle, w_(R) is a half value of a wheel track of the vehicle (w/2, wis the wheel track), and ρ_(R) is the right target curvature.

FIG. 42 and Equations 4 and 5 describe the left rotation driving of thevehicle as an example. In the case of the right rotation driving of thevehicle, since a rotation-inner wheel and a rotation-outer wheel arereversed, the left target curvature and the right target curvature arecalculated according to Equation 6 below.

$\begin{matrix}{\rho_{L} = \frac{\rho_{c}}{1 + {\rho_{c}w_{L}}}} & \left\lbrack {{Equation}6} \right\rbrack\end{matrix}$ $\rho_{R} = \frac{\rho_{c}}{1 - {\rho_{c}w_{R}}}$

When calculating the left target curvature and the right targetcurvature as described above, the controller 20 may calculate a targetsteering angle of each of the four wheels of the vehicle based on eachcalculated target curvature.

Specifically, target yaw rates of a left wheel and a right wheel may berepresented like Equation 7 based on the calculated left targetcurvature and right target curvature.

YR _(des,L)=ρ_(L)ν_(x)  [Equation 7]

YR _(des,R)=ρ_(R)ν_(x)

In Equation 7, YR_(des,L) is the target yaw rate of the left wheel,ρ_(L) is the left target curvature, YR_(des,R) is the target yaw rate ofthe right wheel, ρ_(R) is the right target curvature, and v_(x) is thevehicle speed.

FIG. 43 illustrates an example of a vehicle kinetics model having adegree of 2 freedoms (only front and rear left wheels are illustrated inFIG. 43 , for convenience sake). According to the vehicle kinetics modelof FIG. 43 , the slip angle of each wheel may be represented based onEquation 8 below.

$\begin{matrix}{{\alpha\text{?}} = {{\delta\text{?}} - \frac{{\beta\text{?}v_{x}} + {l_{f}{YR}\text{?}}}{v_{x}}}} & \left\lbrack {{Equation}8} \right\rbrack\end{matrix}$${\alpha\text{?}} = {{\delta\text{?}} - \frac{{\beta\text{?}v_{x}} + {l_{f}{YR}\text{?}}}{v_{x}}}$${\alpha\text{?}} = {{\delta\text{?}} - \frac{{\beta\text{?}v_{x}} - {l_{r}{YR}\text{?}}}{v_{x}}}$${\alpha\text{?}} = {{\delta\text{?}} - \frac{{\beta\text{?}v_{x}} - {l_{f}{YR}\text{?}}}{v_{x}}}$?indicates text missing or illegible when filed

In Equation 8, α_(fl), α_(fr), α_(rl), and α_(rr) are a slip angle of aleft front wheel, a slip angle of a right front wheel, a slip angle of aleft rear wheel, and a slip angle of a right rear wheel, respectively.β_(cg) is a slip angle of the center of the vehicle. v_(x) is thevehicle speed. l_(f) is a distance between the axle of the front wheelof the vehicle and the center (cg) of the vehicle. l_(r) is the axle ofthe rear wheel of the vehicle and the center (cg) of the vehicle.YR_(des,L) and YR_(des,R) are the target yaw rates of the left wheel andthe right wheel. δ_(fl), δ_(fr), δ_(rl), and δ_(rr) are a targetsteering angle of the left front wheel, a target steering angle of theright front wheel, a target steering angle of the left rear wheel, and atarget steering angle of the right rear wheel, respectively, which aresubjects of calculation.

As described above, the present embodiment is a case where a vehiclerotates at a low speed and is subject to a case where the slip of eachwheel does not occur. Accordingly, in Equation 8, α_(fl), α_(fr),α_(rl), α_(rr), and β_(cg) may be approximated as a value of 0.Furthermore, the target steering angle of the left front wheel, thetarget steering angle of the right front wheel, the target steeringangle of the left rear wheel, and the target steering angle of the rightrear wheel may be calculated according to Equation 9 below.

$\begin{matrix}{{\delta\text{?}} = {\frac{l_{f}{YR}\text{?}}{v_{x}} = {l_{f}\rho_{L}}}} & \left\lbrack {{Equation}9} \right\rbrack\end{matrix}$${\delta\text{?}} = {\frac{l_{f}{YR}\text{?}}{v_{x}} = {l_{f}\rho_{R}}}$${\delta\text{?}} = {{- \frac{l_{r}{YR}\text{?}}{v_{x}}} = {- l_{r}\rho_{L}}}$${\delta\text{?}} = {{- \frac{l_{r}{YR}\text{?}}{v_{x}}} = {- l_{r}\rho_{R}}}$?indicates text missing or illegible when filed

The above case is a process of calculating the target steering anglesthe front wheel and the rear wheel in the reverse-phased state. Thetarget steering angles of the front wheel and the rear wheel in theinphase state may be calculated through the following process.

First, the vehicle kinetics model in the inphase state may berepresented according to Equation 10 below.

$\begin{matrix}{{\frac{d}{dt}\begin{bmatrix}\beta \\\Psi\end{bmatrix}} = {{\begin{bmatrix}a_{11} & a_{12} \\a_{21} & a_{22}\end{bmatrix}\begin{bmatrix}\beta \\\Psi\end{bmatrix}} + {\begin{bmatrix}b_{11} & b_{12} \\b_{21} & b_{22}\end{bmatrix}\begin{bmatrix}\delta_{f} \\\delta_{r}\end{bmatrix}}}} & \left\lbrack {{Equation}10} \right\rbrack\end{matrix}$ where$a_{11} = {{- \frac{C_{f} + C_{r}}{{mv}_{x}}a_{12}} = {{- 1} - \frac{{C\text{?}} - {C\text{?}l_{r}}}{{mv}_{x}^{2}}}}$$a_{21} = {{- \frac{{C\text{?}} - {C\text{?}}}{I}a_{22}} = {- \frac{{C\text{?}} - {C\text{?}}}{I}}}$$b_{11} = {{\frac{C_{f}}{{mv}\text{?}}b_{12}} = \frac{C_{r}}{{mv}_{x}}}$$b_{21} = {{\frac{C\text{?}}{I}b_{22}} = \frac{C\text{?}}{I}}$?indicates text missing or illegible when filed

In Equation 10, β and ψ are the slip angle and direction angle of thecenter of the vehicle. For each of factors that define a matrixparameter, reference is made to Table 2 below.

TABLE 2 v_(x) Vehicle Speed m Vehicle Mass I Yaw moment of Inertia IfDistance from the axle of the front wheel to C.G Ir Distance from theaxle of the rear wheel to C.G Cf Front cornering coefficient Cr Rearcornering coefficient

Since a case where the slip angle of the vehicle is 0 is presupposed,Equation 11 is derived because the left side and β in Equation 10 become0.

$\begin{matrix}{\begin{bmatrix}\beta \\\Psi\end{bmatrix} = {{{\begin{bmatrix}a_{11} & a_{12} \\a_{21} & a_{22}\end{bmatrix}^{- 1}\begin{bmatrix}b_{11} & b_{12} \\b_{21} & b_{22}\end{bmatrix}}\begin{bmatrix}\delta_{f} \\\delta_{r}\end{bmatrix}} = \text{ }{\begin{bmatrix}\frac{{- a_{22}b_{11}} + {a_{12}b_{21}}}{{a_{11}a_{22}} - {a_{12}a_{21}}} & \frac{{- a_{22}b_{12}} + {a_{12}b_{22}}}{{a_{11}a_{22}} - {a_{12}a_{21}}} \\\frac{{a_{21}b_{11}} - {a_{11}b_{21}}}{{a_{11}a_{22}} - {a_{12}a_{21}}} & \frac{{a_{21}b_{12}} - {a_{11}b_{22}}}{{a_{11}a_{22}} - {a_{12}a_{21}}}\end{bmatrix}\begin{bmatrix}\delta_{f} \\\delta_{r}\end{bmatrix}}}} & \left\lbrack {{Equation}11} \right\rbrack\end{matrix}$

In the condition in which β=0, a relation between δ_(f) and δ_(r) isderived like Equation 12 below.

$\begin{matrix}{{\delta\text{?}} = {\frac{{- l\text{?}} + {\left\lbrack {{ml}_{f}/{C_{r}\left( {l_{f} + l_{r}} \right)}} \right\rbrack v_{x}^{2}}}{l_{f} + {\left\lbrack {{ml}_{r}/{C_{f}\left( {l_{f} + {l\text{?}}} \right)}} \right\rbrack v_{x}^{2}}}\delta_{f}}} & \left\lbrack {{Equation}12} \right\rbrack\end{matrix}$ ?indicates text missing or illegible when filed

The target steering angle of the left front wheel and the targetsteering angle of the right front wheel are calculated according toEquation 9. The target steering angle of the left rear wheel and thetarget steering angle of the right rear wheel are calculated accordingto a relation with Equation 12. Accordingly, in the inphase state, thetarget steering angle of the left front wheel, the target steering angleof the right front wheel, the target steering angle of the left rearwheel, and the target steering angle of the right rear wheel may becalculated according to Equation 13 below.

$\begin{matrix}{{\delta\text{?}} = {\frac{l_{f}{YR}\text{?}}{v_{x}} = {l_{f}\rho_{L}}}} & \left\lbrack {{Equation}13} \right\rbrack\end{matrix}$${\delta\text{?}} = {\frac{l_{f}{YR}\text{?}}{v_{x}} = {l_{f}\rho_{R}}}$${\delta\text{?}} = {\frac{{- l\text{?}} + {\left\lbrack {{ml}_{f}/{C_{r}\left( {l_{f} + l_{r}} \right)}} \right\rbrack v\text{?}}}{l_{f} + {\left\lbrack {{ml}\text{?}/{C_{f}\left( {l_{f} + l_{r}} \right)}} \right\rbrack v\text{?}}} \cdot \left( {l_{f}\rho_{L}} \right)}$${\delta\text{?}} = {\frac{{- l_{r}} + {\left\lbrack {{ml}_{f}/{C_{r}\left( {l_{f} + l_{r}} \right)}} \right\rbrack v\text{?}}}{l_{f} + {\left\lbrack {{ml}_{r}/{C_{f}\left( {l_{f} + l_{r}} \right)}} \right\rbrack v\text{?}}} \cdot \left( {l_{f}\rho_{R}} \right)}$?indicates text missing or illegible when filed

As a result, based on the predefined vehicle kinetics model, thecontroller 20 may calculate the target steering angle of the left frontwheel by using a distance between the axle of the front wheel and centerof the vehicle and the left target curvature, may calculate the targetsteering angle of the right front wheel by using a distance between theaxle of the front wheel and center of the vehicle and the right targetcurvature, may calculate the target steering angle of the left rearwheel by using a distance between the axle of the rear wheel and centerof the vehicle and the left target curvature, and may calculate thetarget steering angle of the right rear wheel by using a distancebetween the axle of the rear wheel and center of the vehicle and theright target curvature.

When calculating the target steering angle of each wheel, the controller20 may independently control the steering of each of the four wheelsbased on each of the calculated target steering angles. In this case, asillustrated in FIG. 44 , the controller 20 may calculate driving torquefor driving the four wheels through feedforward control (understeergradient) and feedback control (PID control) for each of the targetsteering angles and a current steering angle of the vehicle, and mayindependently control the steering of each of the four wheels in a wayto control the driving of the four wheels.

FIG. 45 is a flowchart for describing an operating method in the fifthapplication of the corner module apparatus for a vehicle according to anembodiment of the present disclosure. The operating method of the cornermodule apparatus for a vehicle according to the present embodiment isdescribed with reference to FIG. 45 . A detailed description of aportion redundant with the aforementioned contents is omitted, and atime-series configuration thereof is chiefly described.

First, the controller 20 obtains driving state information and drivingenvironment information of a vehicle through the vehicle informationacquisition unit 15 (S10 e). The driving state information may include avehicle speed and heading angle of the vehicle. The driving environmentinformation may include surrounding image information (e.g., a frontimage) of the vehicle.

Next, the controller 20 calculates information on a distance up to atarget point, that is, a target of a movement of the vehicle, based onthe driving state information and driving environment information of thevehicle (S20 e). In step S20 e, the controller 20 calculates astraight-line distance, a longitudinal distance, and a transversedistance from the vehicle to the target point as the information on thedistance up to the target point, by using the vehicle speed of thevehicle, an offset distance of the vehicle from the middle of acarriageway calculated based on the surrounding image information, andcurvature radius of the carriageway based on the middle of thecarriageway.

Next, the controller 20 calculates target curvature, defined ascurvature of a target trajectory up to the target point, based on theinformation on the distance calculated in step S20 e (S30 e). The targetcurvature may be divided into center target curvature defined ascurvature of a target trajectory based on the center of the vehicle,left target curvature defined as curvature of a target trajectory basedon a left wheel of the vehicle, and right target curvature defined ascurvature of a target trajectory based on a right wheel of the vehicle.Accordingly, in step S30 e, after calculating the center targetcurvature by using the straight-line distance, the longitudinaldistance, and the transverse distance from the vehicle to the targetpoint, and the heading angle of the vehicle, the controller 20calculates the left target curvature and the right target curvaturebased on the center target curvature by using wheel track information ofthe vehicle.

Next, the controller 20 calculates a target steering angle of each ofthe four wheels of the vehicle based on the target curvature calculatedin step S30 e (S40 e). In step S40 e, based on the predefined vehiclekinetics model, the controller 20 calculates a target steering angle ofthe left front wheel based on a distance between the axle of the frontwheel and center of the vehicle and the left target curvature,calculates a target steering angle of the right front wheel based on adistance between the axle of the front wheel and center of the vehicleand the right target curvature, calculates a target steering angle ofthe left rear wheel based on a distance between the axle of the rearwheel and center of the vehicle and the left target curvature, andcalculates a target steering angle of the right rear wheel based on adistance between the axle of the rear wheel and center of the vehicleand the right target curvature. In this case, the controller 20calculates the target steering angle of each of the four wheels in acondition in which a slip angle of each wheel of the vehicle is 0.

Next, the controller 20 independently controls the steering of each ofthe four wheels based on each of the target steering angles calculatedin step S40 e (S50 e). In step S50 e, the controller 20 calculatesdriving torque for driving each of the four wheels through feedforwardand feedback control over each of the target steering angles and thecurrent steering angle of the vehicle, and independently controls thesteering of each of the four wheels in a way to control the driving ofthe four wheels.

According to the fifth application, there is proposed a quantitativecontrol mechanism for independently controlling the steering of each ofthe four wheels by differentially calculating a target steering angle ofeach wheel upon rotation driving of a vehicle to which the fourwheel-independent driving method has been applied. Accordingly, rotationdriving performance and rotation driving stability of the vehicle can beimproved.

A degree of freedom in design can be improved and various types ofpurpose built vehicles (PBVs) can be mass-produced because the numberand arrangement of the first platforms and the second platforms can beadjusted suitably for the type or purpose of a vehicle.

A stable driving suitable for a driving state is possible and a range ofa steering angle, such as rotation at its own position and side driving,can be more widely secured because the corner module can independentlyadjust operations of each wheel.

Various embodiments of the present disclosure do not list all availablecombinations but are for describing a representative aspect of thepresent disclosure, and descriptions of various embodiments may beapplied independently or may be applied through a combination of two ormore.

Moreover, various embodiments of the present disclosure may beimplemented with hardware, firmware, software, or a combination thereof.In a case where various embodiments of the present disclosure areimplemented with hardware, various embodiments of the present disclosuremay be implemented with one or more application specific integratedcircuits (ASICs), digital signal processors (DSPs), digital signalprocessing devices (DSPDs), programmable logic devices (PLDs), fieldprogrammable gate arrays (FPGAs), general processors, controllers,microcontrollers, or microprocessors.

The scope of the present disclosure may include software ormachine-executable instructions (for example, an operation system (OS),applications, firmware, programs, etc.), which enable operations of amethod according to various embodiments to be executed in a device or acomputer, and a non-transitory computer-readable medium capable of beingexecuted in a device or a computer each storing the software or theinstructions.

A number of embodiments have been described above. Nevertheless, it willbe understood that various modifications may be made. For example,suitable results may be achieved if the described techniques areperformed in a different order and/or if components in a describedsystem, architecture, device, or circuit are combined in a differentmanner and/or replaced or supplemented by other components or theirequivalents. Accordingly, other implementations are within the scope ofthe following claims.

While this disclosure includes specific examples, it will be apparentafter an understanding of the disclosure of this application thatvarious changes in form and details may be made in these exampleswithout departing from the spirit and scope of the claims and theirequivalents. The examples described herein are to be considered in adescriptive sense only, and not for purposes of limitation. Descriptionsof features or aspects in each example are to be considered as beingapplicable to similar features or aspects in other examples. Suitableresults may be achieved if the described techniques are performed in adifferent order, and/or if components in a described system,architecture, device, or circuit are combined in a different manner,and/or replaced or supplemented by other components or theirequivalents. Therefore, the scope of the disclosure is defined not bythe detailed description, but by the claims and their equivalents, andall variations within the scope of the claims and their equivalents areto be construed as being included in the disclosure.

What is claimed is:
 1. A corner module apparatus for a vehicle, thecorner module apparatus comprising: one or more processors configured toobtain a steering angle, and obtain a lever ratio indicating whether afront wheel and a rear wheel of a bicycle model defined with respect toa vehicle are inphase or reverse-phased and indicating a steering angleratio; and a controller configured to calculate a front wheel headingangle of the bicycle model from the steering angle, calculate a rearwheel heading angle of the bicycle model based on the calculated frontwheel heading angle and the lever ratio, calculate first to fourthtarget angles of a left front wheel, a right front wheel, a left rearwheel, and a right rear wheel of the vehicle by expanding the bicyclemodel to a four-wheel vehicle model, and independently control steeringof each of the four wheels of the vehicle by using the calculated firstto fourth target angles, wherein the calculation of the first to fourthtarget angles is determined in differentiated ways based on a value ofthe lever ratio.
 2. The corner module apparatus of claim 1, wherein thecontroller is configured to calculate the front wheel heading angle bymultiplying the steering angle by a preset value of steeringsensitivity.
 3. The corner module apparatus of claim 1, wherein thelever ratio has a value of −1 to 1, a sign of the lever ratio indicateswhether the front wheel and the rear wheel of the bicycle model areinphase and reversed-phased, and a size of the lever ratio indicates asteering angle ratio between the front wheel and the rear wheel of thebicycle model.
 4. The corner module apparatus of claim 3, wherein thecontroller is configured to calculate the first to fourth target anglesby determining a steering control mode in differentiated ways based onthe value of the lever ratio, and wherein the steering control modecomprises: a front-wheel steering mode corresponding to a steeringcontrol mode when the lever ratio is 0; a four-wheel inphase steeringmode corresponding to a steering control mode when the lever ratio isgreater than 0 and equal to or less than 1; and a four-wheelreversed-phase steering mode corresponding to a steering control modewhen the lever ratio is equal to or greater than −1 and less than
 0. 5.The corner module apparatus of claim 4, wherein, in the front-wheelsteering mode, the controller is configured to calculate the first andsecond target angles by applying the Ackerman geometry model to thefront wheel heading angle, and calculate the third and fourth targetangles as a neutral angle indicative of a longitudinal direction of thevehicle.
 6. The corner module apparatus of claim 4, wherein, in thefour-wheel reversed-phase steering mode and the four-wheel inphasesteering mode in a state in which the lever ratio is greater than 0 andless than 1, the controller is configured to (i) calculate the first andsecond target angles by applying the Ackerman geometry model to thefront wheel heading angle, and (ii) calculate the rear wheel headingangle of the bicycle model by applying the lever ratio to the frontwheel heading angle, and calculate the third and fourth target angles byapplying the Ackerman geometry model to the calculated rear wheelheading angle.
 7. The corner module apparatus of claim 4, wherein thecontroller is configured to calculate the first to fourth target anglesas the front wheel heading angle in the four-wheel inphase steering modein a state in which the lever ratio is
 1. 8. A method of operating acorner module apparatus for a vehicle, the method comprising: obtaininga steering angle; obtaining a lever ratio indicating whether a frontwheel and a rear wheel of a bicycle model defined with respect to avehicle are inphase or reverse-phased and indicating a steering angleratio; calculating, by a controller, a front wheel heading angle of thebicycle model from the steering angle and calculating a rear wheelheading angle of the bicycle model based on the calculated front wheelheading angle and the lever ratio; calculating, by the controller, firstto fourth target angles of a left front wheel, a right front wheel, aleft rear wheel, and a right rear wheel of the vehicle by expanding thebicycle model to a four-wheel vehicle model; and independentlycontrolling, by the controller, steering of each of the four wheels ofthe vehicle by using the calculated first to fourth target angles,wherein the calculation of the first to fourth target angles isdetermined in differentiated ways based on a value of the lever ratio.9. The method of claim 8, wherein calculating of the front wheel headingangle and the rear wheel heading angle of the bicycle model furthercomprises calculating the front wheel heading angle by multiplying thesteering angle by a preset value of steering sensitivity.
 10. The methodof claim 8, wherein the lever ratio has a value of −1 to 1, a sign ofthe lever ratio indicates whether the front wheel and the rear wheel ofthe bicycle model are inphase and reversed-phased, and a size of thelever ratio indicates a steering angle ratio between the front wheel andthe rear wheel of the bicycle model.
 11. The method of claim 10, whereincalculating of the first to fourth target angles further comprisescalculating the first to fourth target angles by determining a steeringcontrol mode in differentiated ways based on the value of the leverratio, and wherein the steering control mode comprises: a front-wheelsteering mode corresponding to a steering control mode when the leverratio is 0; a four-wheel inphase steering mode corresponding to asteering control mode when the lever ratio is greater than 0 and equalto or less than 1; and a four-wheel reversed-phase steering modecorresponding to a steering control mode when the lever ratio is equalto or greater than −1 and less than
 0. 12. The method of claim 11,wherein calculating the first to fourth target angles, when the steeringcontrol mode of the vehicle is the front-wheel steering mode, furthercomprises calculating the first and second target angles by applying theAckerman geometry model to the front wheel heading angle, andcalculating the third and fourth target angles as a neutral angleindicative of a longitudinal direction of the vehicle.
 13. The method ofclaim 11, wherein calculating of the first to fourth target angles, whenthe steering control mode of the vehicle is the four-wheelreversed-phase steering mode or the four-wheel inphase steering mode ina state in which the lever ratio is greater than 0 and less than 1,further comprises calculating the first and second target angles byapplying the Ackerman geometry model to the front wheel heading angle,and (ii) calculating the rear wheel heading angle of the bicycle modelby applying the lever ratio to the front wheel heading angle, andcalculating the third and fourth target angles by applying the Ackermangeometry model to the calculated rear wheel heading angle.
 14. Themethod of claim 11, wherein calculating the first to fourth targetangles, when the steering control mode of the vehicle is the four-wheelinphase steering mode in a state in which the lever ratio is 1, furthercomprises calculating the first to fourth target angles as the frontwheel heading angle.
 15. A corner module apparatus for a vehicle, thecorner module apparatus comprising: one or more processors configured toobtain a steering angle, and obtain a lever ratio indicating whether afront wheel and a rear wheel of a bicycle model defined with respect toa vehicle are inphase or reverse-phased and indicating a steering angleratio, the lever ratio being configured to be changed based on amanipulation input; and a controller configured to calculate a frontwheel heading angle and a rear wheel heading angle of the bicycle modelbased on the steering angle and the lever ratio, calculate first tofourth target angles of a left front wheel, a right front wheel, a leftrear wheel, and a right rear wheel of the vehicle by using the frontwheel heading angle and the rear wheel heading angle, and independentlycontrol steering of each of the four wheels of the vehicle by using thecalculated first to fourth target angles, wherein the controller isconfigured to calculate the first to fourth target angles as values thatvary depending on transition of a steering control mode in response tochanges in the lever ratio.
 16. The corner module apparatus of claim 15,wherein the transition of the steering control mode is in response tothe lever ratio being changed in a process of the vehicle driving. 17.The corner module apparatus of claim 16, wherein the lever ratio has avalue of −1 to 1, and wherein the steering control mode comprises: afront-wheel steering mode corresponding to a steering control mode whenthe lever ratio is 0; a four-wheel inphase steering mode correspondingto a steering control mode when the lever ratio is greater than 0 andequal to or less than 1; and a four-wheel reversed-phase steering modecorresponding to a steering control mode when the lever ratio is equalto or greater than −1 and less than
 0. 18. The corner module apparatusof claim 16, wherein when the transition of the steering control mode iscaused because the lever ratio is changed in the process of the vehicledriving, the controller is configured to perform the transition of thesteering control mode during a preset excess time by controlling changespeeds of the steering angles of the four wheels at a preset controlspeed.
 19. The corner module apparatus of claim 15, wherein thecontroller is further configured to calculate the front wheel headingangle of the bicycle model from the steering angle, calculate the rearwheel heading angle of the bicycle model based on the calculated frontwheel heading angle and the lever ratio, and calculate the first tofourth target angles of the left front wheel, the right front wheel, theleft rear wheel, and the right rear wheel of the vehicle by expandingthe bicycle model to a four-wheel vehicle model.